It has been quite a while since I installed Uniframe but from what I remenber it was a pretty decent window. Simonton is also good in the high end models with some upgrades like superspacer.
Stop on in to the Naperville Home Show next weekend if you want and you can see some of them side by side to check out the features in the same room. That might be a good way to help you compare the features between brands.
BTW, if you or any other homeowners here are going to that show, I get about a dozen free tickets from the promoter in my sign up pack. I'd be happy to send a couple to anyone going. Just email me with a mailing address and I'll get them right out. It will save you some dough. email@example.com