Well i raced MECA round 4 with a brushless motor here are my thoughts...
1. NOT enough bottom end, it may have cost me around about 1/4 to 1/2 a second per lap. The guys that turned up for MOD at MECA 4 are Sydney's best racers and in this type of competiton, lack of punch matters. I qualified 10th just seconds out of the A's.
2. Top speed...very good similar to a 10 or 9?, the guys with 7's and 8's had legs on me.
3. Runtime, after each 5min race my packs had about 1min left at 20amps...not as much left over as i had expected. My cells for MECA 4 were Ultra Metal 3000's certainly not lacking runtime and voltage. (if driven at a less frantic pace runtime could be stretched, but i'm not in the business of running enduros)
4. Motor temp after each run was very good, nothing like the usual temp after a 5min mod race for a brushed motor.
5. Cell temps, again very good after each 5min race.
6. General operation, well i did nothing to the motor all day, no timing to adjust (speedo controlled), no brushes to replace, no comm to true.
To sum up the motor was very good, very smooth, but it's not ready for serious competition at the pointy end of modified, for club meets and general RC racing / recreation, the motor is perfect.
So next weekend at the HPI challenge at Forestville i'll be back to my trusty 10x3, and back at the pointy end of modified

(on rubber tires...don't get me started on that one...

)
My next trip into brushless will be the 100,000 rev limited Novak SS..could be a weapon!