I've been looking into the Strobe slipper a little more, and found that some people (Mike included) say that they have run a 9L motor with the stock spur (12 pegs and fully tightened), and not had any real problems with it. I will get the Strobe slipper eventually, but thought I would try the stock setup again as I have a spare spur.
As the first one burned up so quickly, maybe I had the mesh too tight/loose, or the slipper nut wasn't as tight as it could have been? I am also thinking that I may be geared wrongly, after reading some posts about gearing brushless setups on this forum. It is currently geared 16/66, which due to lower gearing of the UE diffs, would be 13-14/66 with stock diffs. The last time I got a full run out of the truck, and took a temp. reading, I think the motor was around 170*F, which is in the upper range of safe temps. My instincts would tell me to gear down more, but I think gearing up might be worth a try, as brushless is different to conventional thinking... :W:
P.S. If it makes any difference to gearing suggestions, the truck is just under 12 lb's RTR on stock Revo wheels/tires, but I have now also got a Hurricane/Response set, which knock a full 10oz. off that weight. :D