I actually have been using the manual avent isis pump because I get more than with the medela pump in style. It's weird because I thought electric pumps worked better but I believe it is also the cushion that the avent pump has that helps. I got 1 1/2 ounces from just one breast usually its 1/2 ounce to an ounce from both. It's annoying to have to use the manual but there are pros to it that its quiet and very small.