DR and AP are fine, no doubt. I have to edit on all of them. Anytime I'm not on FCPX I miss FCPX and wish I was using it. It's all a matter of taste. I love FCPX. I wish the updates were bigger but it's just my preferred NLE.
My theory is that Apple set it up as a loss leader to lure people away from Adobe Premiere. I don't know if that's been entirely successful, as every time I talk to someone who edits video a lot, they're on Adobe.