Get more batteries and bring your patience!
352210
Pretty much everything the others have said is true, in my experience.  The things that make the DP's fun and challenging for some are exactly the things that make others crazy.  It's completely understandable, if one were to randomly buy a DP camera without researching it.  I grew up with 35mm Pentax, when the built in light meter was new and was the first thing the camera helped the user do.  Using the DP cameras (I have all three) are challenging, feel almost instinctual to and old filmie.

**************
Battery life is the thing that could use improvement.  Get extras if you shoot 200 or more photos in a session/day, that's as far as the two (2) included batteries will go dependably if you use the screen as viewfinder...about a hundred (I've had as few as 80) clicks per battery.  Without using the screen to view-find, as many as 200 shots/battery are possible.

The Merrill models use the Sigma BP-41 batteries.  When those were not available I learned the Ricoh DP-65 work, too.  Now there are several companies making and/or selling aftermarket batteries that mostly are at least as good as the Sigma batteries.

The non-Merrill models use the Sigma BP-31 batteries, with the same shutter-click-per-battery challenges as the Merrill units do...and are also now available as generic/third party items.  Get more, if you take 100 or more photos at a time.

All of the above reflects my personal experience, and I'm no pro!
3655754
Every thing just takes too many deferent batteries... once we got all the batteries we love playing with the kit..
3695234
These lights worked great - at first. It seems the batteries come out of contact with the holder. I have to remove them from the railing and tap them down, or worse use a tiny screwdriver to open the case and pop the battery into place. If they can correct the problem with the battery contacts then this would be a great unit.
1600653
After pushing as hard as I dared to get the batteries to seat, I took a loupe and looked at the pins on the new batteries.  There was so much GLUE! holding the contacts in place that the pins would not line up with the connector on the camera!  After taking a razor knife and pulling off much of the GLUE, they eventually seated but I will only use these pigs when I have no other recourse.  Save yourself pain and get the real thing from Panasonic.  I will next time.
4059166
I've called technical support several times about it's propensity to CHEW up batteries, I've had it for about 2-3 months and have replaced the 2 AA batteries 5 times so far.  This needs to be rechargeable or for the battery drain to be remedied.
3836328
Mine are kinda fussy. The batteries seem to get sucked up really fast, and if you forget to turn them off one night, they are toast. After replacing batteries 3 times in each over a couple months, I gave up on them.
4872930
I had the same issue with my Twine that everyone else had, i.e. the batteries only lasted, at most, two weeks.  It was even worse when I used rechargeable batteries.  I didn't know this at the time, but most rechargeable AAA batteries are only rated at 1.22V, not 1.5V.  My solution was to go to Radio Shack and buy a holder for two D batteries, which cost me less than $3.  I then soldered the battery holder's leads to the back of the Twine's battery contacts (see pics).  This was most easily accomplished by taking the Twine entirely apart, i.e. I took off the rubber sleeve and even popped the circuit board out of the white hard case.  I made this mod' on May 9th, 2013.  As of July 10th, 2013, my Twine has sent out over 832 messages and responded to numerous dashboard inquiries, and the battery meter still reads at 100%.  I am expecting the D's to work for at least 6 months, maybe even longer, especially since Supermechanical put out a firmware upgrade and changed the dashboard refresh rate rate from 1 minute to 20 minutes in early June 2013.  To mount the battery holder, I just used a couple of sheet-metal screws through the holes in the back of the holder.  Same deal with the Twine.  I took some plumber's tape, made a little bracket, and then screwed it to my garage door with some sheet-metal screws.  Problem solved, and for less than $3 and a half-hour's time.
364724
I don't review a ton of products but wanted to warn people looking to buy these.  A lot of others have mentioned the batteries start having issues after awhile.  I do not believe that it is as much the battery as the connection from the base to the battery.  About every 2-3 weeks, I have to clean the contacts on the back of the controllers with alcohol to get them to charge properly.  It works about 70% of the time.  Also when placing them in the dock, you almost have to move them around until the light comes on. There is also a delay on the light so it can be extremely frustrating and time consuming.  I also purchased two of these (as i have 4 controllers) and it seems that the first one I received (same model and brand) is slightly different than the second so I end up having to make sure the correct controllers are connected.  I want to be clear that these worked pretty well for the first two months and have been nothing but trouble since.  I understand that Microsoft made the charging interface more difficult for third parties to try and sell more official charge and play kits but this is not the answer....
4883544
Great little tool, when it works.  The second day I had it it wouldn't turn on until I'd put it in my chest pocket for a couple hours and it warmed up.  Next two days that didn't make a difference, it worked when it wanted to.  I'm a fleet mechanic, so it needs to work when I need it to, not when it wants to.  Maybe it got hammered in shipping, I don't know. I emailed the seller, and while waiting for a response,  I'll try and figure out what it takes to make it work.
UPDATE: This is going to sound silly, but after removing and installing the battery a few times, noting it would usually work once each time after reinstallation, I put a NEW battery in, and it has worked fine for a few weeks now. So, if yours doesn't work, try a new battery!
182976
No instructions so remember to open each light and remove the paper circle covering the battery before testing. Over half the lights didn't work at first. The problem has to do with a bad connection between the light and the battery caused by small plastic barbs keeping the lids from closing enough and/or the battery connector (2 metal posts on opposite sides of the battery) not high enough to make contact. I removed the barbs and pulled up on the metal posts. After that all lights worked except for one. In that case the metal posts had to bend the ends upwards so they contact the light. Not sure why the quality was so poor but they eventually worked with a little effort and TLC :)

If you remove the barbs and bend the posts and light still doesn't work, trying testing the light with a base that is known to work. If the problem still exists try removing the light from the lid and placing on top of the base so the middle of the battery comes into contact with the spring and the posts come into contact with the outside of the light. If the light does on the problem is still with the connection. Try bending the end of the posts a little more and pull up gently on the post to get it to move up a little. You can also add a little piece of paper to the bottom piece by removing the batteries and pulling out the positive terminal by pulling up on the posts. Add piece of paper under the negative terminal. That should help raise the posts to the correct height. Put back the terminal and battery Positive sides down and try again.

I also added a small amount of coconut oil around the white O-ring to help keep out water/moisture. I even Seal-a-meal'd a few and tossed them into the pool. Even in the Seal-a-meal package they were easy to turn on and off with no fear of being water damaged :)

Hope this helps someone. Practice gratitude daily :)
1647651
Expect to change the batteries often. Cold weather is even worse on battery life.
446229
I've used this device for about 3 months and have had to change the batteries in the remote sensor at least 5 times.  I wonder if it's defective, or if you are expected to change the batteries every 2-3 weeks--that runs a little bit too expensive for me.  I'm going to pitch it out and hope to find a suitable replacement.
3873903
I initially had a problem with very poor battery life (lasted one day off the charger), but after a conversation with customer support yesterday, I believe (I hope) that problem may be a thing of the past.

1.)  Holding the ON/OFF button, remove the battery, then reinsert it before letting go of the ON/OFF button.  It will now show you to be in Safe Mode.  (If you decide not to finish this procedure, remove the battery and reinsert to get out of safe mode.)

2.)  Log into your Logitech account, click on Downloads, then click on Firmware.  You will now plug the USB cable in, and follow the instructions.  (No different than when you update your remote codes.)

I'm on the second day with the remote still showing fully charged, where before it was dead after 24 hours.  (Some people may not care about this, but I would rather replace batteries once every month or two than be forced to cradle it every night...)

Hopefully this solved the battery life problem for you as (I think) it did for me.  This is still such a new remote, they are continually working on the firmware to improve it and fix problems.  (For a later improvement, how about giving it a delayed "System OFF" that could be used as a sleep timer?)

That being said, I do love the remote.  It doesn't function any better than my 880's (I have two of those), but the button layout is so much better (easy to operate without looking at it to find the correct buttons).  The touch screen really isn't any more functional than the other Harmony remotes that don't have it, but I suppose they put it in for the techno-geeks who want a touch screen on their remote.  I would have been happy with large, easy to hit buttons around a regular screen, with the RF capability.  We all know the next version will have the RF added to it (880/890), and from what I have heard, they already have provisions on the circuit board for it.  They just want us to buy this one, and then the RF version.  I personally don't appreciate that kind of marketing, I would have rather had a choice of a RF or non-RF remote.
1101103
Convenient, great customer support. The camera is not always clear though.

Also, my batteries lasted from 6/19 to now 8/7. Not even 2 months! Set to recording 20 seconds at 60% sensitivity (driveway). seems like it should last much longer :(
2360165
I used the solution in my batteries and after some 10 days I could feel more power in my cart and batteries did not discharge so fast.  I did notice the fluid in my batteries turning brown, maybe the deposits are coming loose.
892269
I purchased 2 sets of those on May 30 and they had a battery problem where batteries wouldn't hold the charge and the devices turned off every time you transmit. I contacted midland and reported the problem. They asked me to put regular batteries and try the devices. they worked like charm So Paola from midland told me they will send me new batteries within 2 weeks. 4 weeks later i maild Paola and asked her if they are not sending the batteries i will return the products for a refund as there was still a couple of days before the return windows closes. But surely she assured me that batteries will be shipped soon.
As my return windows ended. on july 1'st i received the following:
"Good Morning Toufic, I have sent some spare batteries out to you since the new ones have not arrived yet from overseas. This sometimes takes a while. I will try to keep you updated once I am updated.
 Thank you for your patience,"
Guess what ?? the batteries she sent are all defected batteries that had the same problem as mine.
Answers i received while asking for the replacement batteries during the 4 month:
" Thank you for contacting Midland Radio Warranty Service Department. I am sorry to hear that the batteries have been giving you issues. There are batteries currently on order and should arrive in about a week. Once they are in, I will have 2 sent to you. Until then, your units can work on 4-AA alkaline batteries."
"I have not received the batteries yet. I am not sure what is the status is but I will check. I can only provide you information that has been giving to me."
"The batteries have not arrived yet. I should find out more information about the shipment tomorrow."
3467089
2 of the sensors are on the fritz already. Not sure if its batteries or not  -  but even if it is, they have only been out for a week!