[lorinda]

I suspect the AT is slightly more valuable because bad players will call raises with Ax and either have to fold to a continuation bet (assuming they are bad/good enough that they don't stop/go) or call when they are dominated, while when you have KQ, they can actually sometimes outflop you with their Ax and there is nothing you can do about it.

Edit: Also, KQs loses some of it's suited value here because you will not always get to the river.

Lori