Worked well with liquids
587757
Used these for potions at our son's wizard-themed party. Used a regular funnel to pour liquids into each bottle. Stoppers are easy to take in and out, but stayed put when the kids were running around with them. Cork soaked up some liquid after leaving it on its side for a few days, but no leaks.
2564976
We bought these for a science experiment and now I use them to test different bottled waters. I got some surprising results!
1973816
I use this and a picnic tap to dispense carbonated water from a 5 gallon keg. It works well to keep the bubbles from getting out of control.
887632
Worked well to get rid of pet stains and simple to use. My only gripe is that the water reservoirs are impossible to air out and dry. After leaving them open and trying out different positions, they were still wet after a few days. I'm concerned this will cause nastiness to grow or accumulate.
3324882
These bottles are great for runny liquids but not for thicker things like icing as I had hoped. I like these because they're food safe and I like to decorate my baked goods. Unfortunately I found the bottles difficult to squeeze. The description had said it would be possible to create precise designs, but that requires thicker liquids that have a tendency to "stick" inside the bottle.

Pros:
Cut your own tips so you can choose the size
Comes with little caps for each bottle
BPA free
Durable material

Cons:
Rigid walls are hard to squeeze
Lots of shaking required to empty the bottles
1968686
Used these while away for 5 weeks (with a 64 ozs. plastic soda bottle reservoir) and they worked great! (I wouldnt recommend going beyond that period of time bc the water will run out.) I placed all my plants in the tub, just in case a bottle fell over. No leakage, and plants remained moist! Follow the instructions and make certain the tubes are down far enough into the soil.
They would make a wonderful gift!
105739
I bought these to use to water my office plants while on vacation. They did the trick with all plants surviving and no need for co-workers to take time out to keep them alive. The only drawback is that it can be difficult to determine where on the sticks to punch in the holes and how many. Instructions on how high up, how many holes for the size of the pot, etc. would be helpful. One suggestion I have to to make sure your plants are thoroughly watered before using these. My poor little plants went through the bottle of water quickly -- very thirsty. But once watered, these worked great and fed the water slowly (I'm assuming -- came back with lower levels of water in the bottles).
3438685
I used it for water bottles and it worked for my daughter and I during summer break. The only thing that bothered me was the smell that never went away. Every time I drank out of the bottle I would smell it
3531849
I bought these mainly to store homemade simple syrup for my Tom Collins habit, but have used them for several other liquids as well (half and half, lemon juice, etc). These are also great for transporting small amounts of liquids you use, for example, I have to have half and half with my coffee and will bring my own in one of these if buying a carton isn't feasible. These have traveled down bumpy ranch roads in the bed of a pickup with nary a drop spilled. Easy to wash (I only handwash), these are super handy and will likely purchase more in the future.
3758475
These worked just fine in the 750ml Torani syrup bottles. You do have to pour out a tad of the syrup otherwise it'll spill over. And they don't quite reach the bottom of the bottle. But this isn't a huge deal to me.
813329
Good brushes for loose liquids, I got them to apply epoxy to fishing jigs. Epoxy is very thick and sticky which pulls out several bristles. I rip them in a vice before I use them which really helps but still not perfect.
3033466
This product worked where the liquid alternatives failed!  Very satisfied with this purchase - will purchase again when I need.
1704428
I purchased several sets to use at an event where my makeup class did face painting to entertain young children. Using a little bit of water along with the paint made it work like gangbusters. There was no mess and the colors were bright and easy to use. The stencils were hit and miss, but the paint was top notch. I'd recommend it.
2113295
Worked great for my 10 year olds science project. We used them to test

Orange Juice
Tomato Juice
Vinegar
Milk
Soda
Water

All tests came back with results in the expected ranges
3956747
The liquid product works great.  I have music from a cassette deck that had been on life support.
The cassette tape itself broke before I could use it/  I used an old one I still had and it worked.
4180219
4.5 Stars: This MUST be used with a Liquid Feeder or Universal Feeder attachment for your garden hose.  It cannot be used direct from bottle.  I deducted half a star some of the instructions/information provided is in a light blue shade which is close to the color of the bottle itself and makes reading difficult in spots.  You use this once a week on flowering trees and shrubs for longer lasting and bigger blooms.  This is specifically for acid-loving plants but I used it across my front which is made up of azaleas, rhododendrons and others.  I think two of them are pictured on the front and I hope it works across the board as my shrubs blend into each other.  After two weeks of use, I see little improvement but will report back after continued use.
1248469
I purchased over 100 of these for a kids day project. They are super easy to plug in to a recycled Coke bottle, but about 20% of them leaked. Not sure if that's a human error in our part to do with suction or vacuum created in the bottle or manufacture defect. I gave 4 stars because overall this product did as it was intended, just not entirely clear as to the reason why some continuallydripoed until empty.