What was the fastest Windows Mobile Device to support AT&T

Before Windows Mobile was replaced by Windows Phone, what was the fastest (network-wise) Windows Mobile Device to support AT&T's 3G network? I always thought the old HTC Tilt2 that I had was the best they had to offer (hah....with it's miserable speeds), but my buddy said he had the HD2 on T-Mobile and got superior speeds to mine. So I am wondering what WAS the fastest WMD phone on AT&T?

:)