I have been following this discussion re: different pumps resulting in different milk yields. I work at two different sites that rent pumps. One site charges the same for both pumps the other charges quite a bit more for the classic. I see mothers who definately experience more luck with the classic and have informed the manufacturer of this. The pity of the situation is that at the site where they charge more for the classic we hesitate to give it to them and I have been questioned about it when I did. I often feel like I am taking advantage of a mother who is already in a compromised situation by charging her more. Denise Parker