I did the Gree stuff (not PvP) on 4 different toons tonight, 2 times mainly solo and 2 times in groups. Even did the heroic once solo. Found everything extremely easy, with the exception of doing the heroic solo with my healer without the use of flyby. Never any danger of dying, but it took forever because I couldn't use 2 of by best attacks for fear over flagging myself.
No lag or crashes on my end.