For what my advice is worth, I am mounting 3 graupner speed 600 bb motors in my 48 inch x 12 inch PT boat. I have separate waterproof speed controls for each motor that have 100 amp forward continuous current capability and 60 amp reverse continuous current capability. (purchased them from Ebay for $20.00 per ESc. Bought 20 to get the bulk price. I want to build a lot more boats.) I have purchased three 10 DCell battery packs that are 12V10AmH to run the boat (very big expense $119 each). Should give me an hour run time at full throttle the three weigh about 10lbs total, but I need the weight to keep the front of the boat at a reasonable angle when on plane at full throttle. My stuffing boxes and shafts are Roboesch products. Shaft size is .04 mm designed for 25000 RPM. The props are also Roboesch 45 mm three bladed left hand props. I'm in the process of mounting the shafts in the boat right now and suspect that it will be very fast for a military type boat. I selected the ESC size because the motors are rated for 30 amps continuous current each and I didn't want power spikes to fry the battery or the ESC. I will still have to run fuses for each motor. I am using a receiver and transmitter from Polk Hobbies