We got the Graco Comfort Sport. It is the biggest pain in the butt to get in initially, but once you have it figured out, it's a breeze getting it in and out. The things I do like about it are that it fits in my car (I have a Dodge Neon) and it seems to be comfy for her. It's padded really well, so she's not sitting on hardness. We have a Costco Scenera for my MIL's car and it just seems really hard. We only got it because it's only used for emergencies.
I've heard wonderful things about the Safety 1st Alpha Omega and the Evenflo Symphony too.