Instruct: Classify Amazon reviews into positive or negative sentiment
Query: They are more work ,but seem to work well

I only use these bottles, my daughter would not take any other ones right from the start. I can not compare to other brands but I can tell you that she doesn't spit up, which may be her naturally, but I wouldn't switch from these bottles just in case. They are more work to clean ,but if you buy enough they can be put in the dishwasher so it really isn't a big deal. I also read other reviews about leaking and can honestly say I have never had a single leak. There is a line on the bottle that says not to fill above and also for travel they provide a "travel disc" to fit under the nipple to prevent leaks so I am not sure how other people have all these problems. I really think these are a great product and certainly worth trying!