I use Mango and it is really snappy and fast, the phone I got it on is the Dell Venue Pro which also has a curved glass display and that screen is wow the only two things that suck besides having to jailbreak via microsoft is no bluetooth filesharing and on this phone the camera is the worst camera I ever had in my life! Other than that, the fb/hotmail/skydrive/twitter integration is awesome, I connect to wifi and everything syncs. It's pretty cool. I believe microsoft did a couple lil things that kina sucks but the speed u get from these things that seem weird makes up for it. Like I would love active multitasking, but then they might need more ram and a better processor ? idk not too sure so they use that pause the app thing which works well for me.