I used the Clevelands for ages and loved them but one day I was hanging around in the pro shop and the guy behind the counter gave me a good offer on the ATV's, buy 3 get 3 and a sleeve of Nike L71 balls thrown in for a mere 450 credits more ; )
I do like the ATV's, great meter and forgiveness and the slight lack of spin is no hardship 95% of the time. If anything it makes judging distance a bit easier. I'm still getting used to playing pitches with the 64° though, the Cleveland would let me hit the ball right to the hole and stop it dead, the ATV doesn't manage that quite as well. The other area the Clevelands were better is squeezing a few extra yards out of them, I could easily get 6 or 7 more out of the 100 yard Cleveland by using top spin, the ATV won't get more than 2 or 3 unless it's to an elevated green when you do get a bit more roll out.
Unless you're drowning in credits or having trouble dinging your Clevelands I'd stick with them, there really isn't much gain to be seen for 3600 credits.