No, if you don't have the 8800, don't load its OS. An upgraded 4.2 OS is available per the sticky note at the top of this thread, specifically made for the 8700.
Yeah. I've tried both V & C. I need myFavs to work. Someone said I can simply switch "my phone" on t-mobile.com to a myfavs phone and edit my myfaves list (with the plan activated of course) there? Can someone confirm if this is true? I dont want tmo closing my account or anything!