Healed with blizzard standard UI since release, and still going strong (well, alright, if you must nag me like that, I did use CT-raidframes in the start.) Blizzards standard UI with some minor tweaks (mostly for arena, like proximo and magictrax) which are the only addons I find mandatory for me to play optimal. I tried mazzel - was waaaaaaay too many things going on, and I could never get used to the HUD, but I guess thats all about preferences.