I'm running GB 2.3.3 via CM7. It has been much smoother than any Sense-based ROM I've ever configured (Including the one on your sig EarlyMon), so if you're rooted, I would definitely suggest giving the latest stable CM7 a try. The CM functionality is pretty isolated, so you can choose not to use much of it (like me) and enjoy a very AOSP experience.
I used to be a rooted stock HTC ROM (w/ custom kernel) user. CM7 changed my outlook. But the only reason I decided to give it a try was because I heard that everything was working. And indeed everything works.
I've removed my dependency on HTC widgets long ago when I started to favor ADW launcher over Sense's launcher. So switching to AOSP was easy. And the fact that CM uses ADW as the default launcher made it even better for me.
There were some Sense-based system sounds that I missed, so I copied those onto the CM filesystem. Now I'm right at home.
GB is mainly a polish release. Lots of usability enhancements, a little bit of aesthetic improvement, especially in the status bar (hated the old AOSP look). Stock apps are improved, especially the dialer.
I'm also looking forward to a BT mouse cursor. I suspect it may never come to the Evo though.
So yeah. Flash CM7 and get a proper taste of Gingerbread. If you don't like it, well... then you won't care as much when it officially arrives on the Evo. Maybe