I just got an Atlas MP-15DC and have started running it in. Maybe 6 hours total running so far. It really is a good slow speed runner at low voltages. It really creeps at low voltage (less than 4 or 5 vdc. Anything over that, it starts growling. I seem to remember someone posting a modification that "cures" the growling. I may be a little picky on the performance but I plan on getting a couple more once I'm satisfied with the performance of this unit.
