From a Droid 1 and what a difference. I was rooted running bugless beast 0.9 with launcherpro on the Droid 1. Moving into the Rezound I very quickly figured out that I do not like the HTC sense UI. Replaced it with both Launcherpro and Go Launcher and am hemming and hawing between the two. Either is a huge improvement in how fast the phone reacts though.
Only downside so far is that in a two bar 3G only area, I obliterated my fully charged batters in just a few hours.
Upside is that this phone is amazing in every other aspect. Just don't mention the bloatware.
Posting from my Rezound....enjoying the beats.