Conrad-I am actually quite happy with the LRP X12 3.5. I am right on the edge of the envelope power wise. Any more power and leads will desolder, batteries will dump, the motor will overheat. I tried the LRP X12 3.0 and ran the same or slower with more heat evolved by the motor. It would not work in the summer here.
by slotless, you might also mean no steel stack or core. I tested slotless motors from Mamba. That steel core in the LRP and Novak motors raises induction by a huge factor of 10 and makes the motors more efficient. I found the Mamba just ran hot without sufficient power.
I will take a look at the models you mentioned. Here are some links. Note power at 7.2 V is missing
http://demonpowerproducts.co.uk/prod...oducts_id=3949
Here is link to the slotless speed passion motors. I cannot tell if it is coreless or not.
http://www.redrc.net/2010/01/speed-p...red-bl-motors/
In the XXXS I would have trouble with
this motor dragging the ground. The ring on the back end is bigger than the can and the motor appears to be longer than X12. You can already see in the above pic the metal I have removed for clearance.