I've ridden all three and if I didn't already own the RMK I would own the M sled. Just as good in my book the Poo and the AC are a dead heat IMO. Yes Poo does have a bit more motor, but the M is more controllable on a side hill, they both lay over super easy the poo tends to flop too easy sometimes. And at super slow tight tree riding speeds the AC is easier to get on its side for making that "have to" downhill 90 degree turn before you fall in the tree pit maneuver. The AC chassis is amazing, the Poo motor is amazing. I honestly think my next sled will be an M8 cuz the riding I do I need the chassis more than the motor and a few extra ponies aren't hard to find.