I remember running one on a friend's layout many years ago when I first got back into the hobby. Though visually not as impressive as the newer RMT version, I recall it ran well on his layout with no stalling on switch tracks. It came with a single motor and was DC operated though a diode was included so it could run forward only on AC current. The one thing that stands out in my memory, other than the fragile plastic handrails, was the placement of the roller pickups, which were further apart than the RMT version.
There's not a whole lot of information on these, and then I remembered this website, which has some pictured. A neat site as he also has photos of Kusan items and Franks Roundhouse.
http://www.robertstrains.com/WilliamsArmyNASA.htm
Direct link to photos of the original Kusan versions of this loco...
http://www.robertstrains.com/Kusan22.htm
Above is pictured one of the Williams versions of the Mighty Mite, from Robert's web site. If you look closely at the above photo, you can see (as I remembered) the roller pickups (upside down "U" channel mounting similar to what Lionel is using on rolling stock with die-cast trucks) right next to the locomotive steps.
Though the decoration was certainly spartan on these locos with unpainted, molded color shells, I do like the black handrails over the silver ones on the vast majority of the RMT Beeps. Though again, the plastic ones were a bit flimsy and fragile.
Hope this helps.