The ESC and its firmware used with Brushless make so much of a difference, that its very hard to give standard rules or values to how much power you will get out of a system. The reason the ESC's are reflashed is that the standard firmware is pretty dumb in the way it tries to move the motor. Normally these ESC's are used in drones or planes with set max weight and prop values so its all setup for that, but that's no good to us. SimonK and BL-Heli are smarter and can have their settings tweaked to suit your setup.

Both Binky II and Conker 3 run NTM 3536's on Flashed TZ85A's at 4S, on 75mm Wheels, 16:1 gearboxes, and have more than enough drive power for Spinners. I believe we are currently running the default SimonK Values with no issues. I'd also say that Brushless motors are much more forgiving when stalled as you aren't in danger of burning out a single phase. We've stalled 3.7Kw Scorpions on 12S and they've been fine during a 3 minute fight, but we use VESC's, so they can detect a stall and restart. The one time we have blown one up was on an Castle Creations ESC, and every phase burnt out simultaneously due to the power it was dumping into the motor; not a very smart ESC.

I personally can't see the point of over-volting a brushless as they are so powerful anyway. But if you get your setup right they can sip power. To give an example, Binky II ran the most recent FW Gladiator for 5 minutes with a 4S 1.3Ah drive battery and two 2.7Ah 4S lipos for its weapon (Wired to give 8S) In the 5 minutes we used 1000mAh of drive and 1.8Ah on the weapon. We used to run 550 motors on a 2.7Ah 5S, and had to recharge it every fight; wasn't paying attention to the figures at that point so I cant recall how much it used but it was enough that I felt it should be fully recharged.

Take from that what you will. Everyone has slightly different preferences and experiences with Brushless, but hopefully it helps.