In the market for a small practice/possible recording amp (on a tight budget of course) and notice that there are several Crate 15 watt models (GFX, GTX, GT, etc.). Are there any of these better than the other? I am looking to keep it under $100. Perhaps some are designed for a specific tone than others??? Thanks.
Dude, seriously, don't do it. You will hate the damn thing in about a month. The distortion sounds like kazoos, and the clean has the worst sounding twang I've ever heard.

Save up $100 and buy something better.
I had a Crate GT-15, that thing sucked balls though. If I were you I'd shell out about $130 and get a Roland Microcube. It's compact,portable, and it has several effects and distorion settings already built in.