If you could get it for say half the difference, $899 ($900) vs $1700, => $1300, geez, even now that I think about it, that's still a lot of mulah...

I don't know, but I think I'd be willing to bet, that sure, maybe the AT has all those upgraded, hand selected parts, but would you really hear any difference *in real world applications*? I have to (want to ) think not....