I've got an Avent manual and electric. I'm not really expressing anymore, but when I was I would switch between the two. I found I got better suction with the manual, the electric didn't seem to suction as good. I used the electric when I was having trouble letting down, I could just put it on and ignore it and sit on the computer. In saying all that though, I have never been a good expresser, never been able to get much out. Next time, I will consider hiring a Medela from the ABA.