Lew, I haven't yet had the PD444 motor apart for service, knock on wood. The literature describes the motor as flat, slotless, brushless, DC servo-controller with Hall sensors. Like L07D it uses magnetic levitation, in this case to relieve about 4/5 of the 2.5kg platter weight. It has a much lower-torque, lower-current motor than the L07D. The design work is rumored to have been done by Micro Seiki. The motor may be JVC.
I do find the DD sound of PD444 and L07D more appealing than my much modified VPI TNT. With the VPI converted from rubber belts to thread it was possible to tension the thread for a cleaner, faster-paced "DD-like" sound. Both Luxman and Kenwood go further in that direction.