The Denons use an AC Servo direct drive system. All the rest are DC direct drive. The new VPI Direct is an AC servo DD and supposedly is an updated clone of the Denon DP-100. The Denons are widely considered to be the best of the vintage direct drives, especially the DP-100, 80 and 75.
Harry Weisfeld has written himself on AA that the Victor TT-101 DD turntable made in the late 70s-early 80s is the best turntable he's ever heard and together with the Kenwood L-07D inspired him to create his VPI Direct.
Both of these use DC servo motors as far as I am aware...?
The motor Harry uses for the VPI Direct is the Thingap (made by an independent manufacturer) which is also used in the belt drive Continuum turntables.
It is the performance and availability of the motor that promps the usage in the VPI Direct....and not the choice of power delivery.