I posted this in the road bike section, and they politely indicated that there's a forum for commuters. I just didn't notice it. Anyway, I was wondering if anyone would care to help me out a bit:

I'm a grad student, and I intend to use a bike for my primary mode of transportation. I was wondering what everyone thought of a few bikes I found in the local stores. I'd like to spend somewhere between $300-$450, but if something pricier comes with considerable recommendation, I'd pay $550.

Here are some bikes I liked:
Trek 2010 3500 for $360

Giant Rincon for $400, but as I recall it had brake pads rather than disc breaks.

Giant Cypress for $235

and Giant Seek 2 for $525.

If you've got any advice or insight into these bikes, it would be really helpful. I intend to use it to get around everywhere, since I don't feel like owning a car yet. I'd like to be biking in any weather, all year. That means I need to pick up some warmer clothing for the winter, and a mask or something. I keep losing my winter hats...I bike to the store sometimes. So far I've just brought a backpack, which carries enough food for the week, but makes me pretty top heavy. Makes for a more interesting ride =)

There's so much information to try to absorb! I still don't really know all the questions to ask. I'd like to attach fenders and a rack and...whaddaya call 'em...panniers? So as I don't have to hold things.

Thanks so much for reading my post here! Thanks for having patience with a newbie like me! In return, let me answer any burning physics questions you have! OK well, maybe that's for a different forum.