Maybe I just got lucky but I bought 2 computers from ibuypower.com, both for friends, and they've had no problems at all. I haven't found any other vendor that can match their prices. Plus, they have a whole lot of awards from various PC magazines. Of course, since my friends had no problems, we've never had to use their tech support, so I can't confirm/deny whether or not their tech support is any good.
As for case designs, they're all a bit "out there" and if that's not your thing...I can see calling them ugly. That's a personal preference I guess. I think there are a few models that can be configured with a "normal" looking case.
I'm not saying they haven't sold any lemons (what vendor hasn't), I'm just saying I've had nothing but positive personal experiences with ibuypower.com and as far as I can tell, they use all good brand-name parts.