Hello from a current UCSC student. Whether or not you'll be happy with a single speed/fix gear around here really depends on a couple of things: how good your legs are and if you're going to get the bug to ride outside the metro (heh) area of Santa Cruz. I think coming from Chi your going to feel like SC is nothing but hills. You might check out the terrain on google earth.

On a side note, If you live on campus, heading down from campus to the downtown area almost invariably involves heading down Bay Ave, which from what I hear can be a bit hair-raising on a fixie.

If you're living off-campus, well, let me just say if you're not in shape you will be very quickly.

If I was in your situation. I would probably by something cheap and used in Chicago now, and wait til I got out here to buy something new. Or the other option would be just to wait until you got out here. it will save you on the shipping, and in Santa Cruz there are enough bike shops that if you didn't like the one you're at you can walk down the street 10 mins and find another one.