I use a Medela Swing - I borrowed my friend's Ameda something and also my sister's Medela Swing and decided I liked the Medela better.

Its smaller, quieter and I think it has a better pumping system - two phase, it mimics the sucking action of baby with the quicker sucks and then you hit the button when you feel let down and it changes to longer sucks.

I'm not sure how it would work with a Avent bottles but I'd recommend against getting Avent - I'm pretty sure their bottles contain BPA, Bisphenol-A, a nasty chemical used in some types of plastics.

You can get 3 Medela bottles from Target for $20, so they aren't too pricey. The pump itself was $279, I got it on special at Baby Bunting.

Good luck!