Well, my mind is made up, but I thought I'd post my own thoughts for any who might search this out later. I tried aff for about 1 level(60-61) and wasn't doing all that well with it in the outlands(even after I picked up some half decent spell damage gear). Haunt is not nearly as useful as it looks just reading the description, and survivability is an issue if you just use imps as a mana battery and effectively have no pets. I also don't like using fear unless I'm desperate, so perhaps I was making a few mistakes in there

at 61 I switched over to demo, and I can say with certainty that I don't intend to go back. I'm 63 now and loving every minute of it. Felguards are just awesome, both in appearance(not that important, but the cool factor has to play in a little bit), dps and survivability. Also, Metamorphosis+immo aura=more or less instant win in equally matched pvp and especially in pve. I can drag 10 mobs to me in meta form and then pop immo and they all die within 15 seconds. And immo and the huge spell damage increase from meta give me a good edge in pvp. I've had about 30 instances of world pvp in the last few days and lost 3 of them. And even those were only when the enemy was significantly higher, outnumbered me, or attacked me after a particularly nasty fight when I had low hp.

these are just my thoughts, you might have different opinions, and I'm sure things will change once I hit 80 and start instance runs. I just thought it might be helpful to anyone else going the lock route to read my experiences.

PS---an important side note which most of you already know is DO NOT go felguard until level 56, he royally sucks before that and doesn't have any of his abilities. I'd go beyond that even to say not to switch till 60 when you get meta form.