I used this for a few days, but it was too flakey. Ended up with nothing that used location services working (the location services were constantly crashing), and SenseUI was crashing pretty frequently. A reboot fixed things for a while, but they all crept back. Also the mms splitting problems and other quirks like GPS not locking on, 3G problems, Wifi problems, beeb player not working, FriendStream crashing on start etc etc.
Sense2.1 v2 certainly has promise, but right now I am running Villian 5.3 (with the exact same radio firmware) and things seem much more stable and complete.