[BrianG]

Yeah, my Fluke is fused for 10A. Gotta figure these meters are for general purpose measuring, and not for currents in the 100's of amps. You can use clamp style meters, but that's just more cost. And using any meter would require the tester to constantly jot down voltage a current measurements (so would need two meters), and that would not be close to accurate. The Eagletree measures voltage and current using a hall-effect sensor (does not drop any voltage that a shunt would) to measure up to 150A, and can record as fast as 10 samples per second (100ms). For ~$70, the ET device is hard to beat for what it does.

And as far as a non-adjustable BL motor driver, I can think of a simpler way: Use an ESC like J57 said, but use a failsafe device as the throttle driver. They generally have an adjustment pot, but it's meant to be set once.