If you havn't found an answer yet: A few amps isn't going to tax a decent ESC. I have some that can handle "12 turn" motors, which can run at about 36 amps and peak at about 65. The question is whether your ESC can run the low amps you're pulling. I bought this ESC for the slewing function in a crane model, but it couldn't quite run the tiny motor (in the milliamps) at the HYPER slow speed I needed. Still, it would probably work for you in a machine drawing a few amps.
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