I use this pump as a backup pump and a travel pump. I exclusively pump, so I pump a lot. I used this with just batteries for about a week and a half before it kept dying on me and I was unable to pump on the go. I changed the batteries two different times and it still dies. I am going to contact Medela to see if they have a solution. The pump works great if I have it plugged in. I love that the base is small and can be taken anywhere. This pump is very easy to use. A few things I don't like about this pump are the fact that milk can find it's way into the tubing. It hasn't happened to me yet but I have seen condensation in there. I also wish that the bottles came with nipples. I don't use them because I have to transfer the pumped milk in to a bottle to be able to use it. It would be great if I could just use that bottle. I just pump into my other bottles. The flanges are just hard plastic. Not painful but it would be nice if they were a bit more comfortable. I like that this pump comes with a travel bag. It makes it easy to take along. As long as this will work with batteries I would recommend.