I've seen all four of the ladies in the OP and would heartily recommend all of them, for different reasons. Never seen them as a duo though.
Depends what you're after - my gut tells me that AV and Nat would absolutely fucking eat me alive for an hour, whereas an hour with Kendall and AW would be more chilled out but probably more sensual and less extreme. I'm only guessing though.
Either way, you'd be in for a bloody good time!
Can't comment on Logan and Ashley, but Ashely certainly does seem to be getting some excellent reports recently.