For drills, assuming 1 per speedo, you're looking at about a worst-case scenario of 15a draw when stalled (changes a little depending on voltage but you're safe reckoning about 15a). Using that as a rule of thumb, a single speed controller of 15a continuous+ should run a single drill-scale motor safely, in most robot situations. So with that in mind, a 15a Electronize speed controller would control it happily, but the drive precision and bad customer service by Electronize doesn't help their case. That said, we have found the 30a models (more pricey, but still cheap as ESCs go) to be very reliable. They'd hard speedos to break as speedos go. They just result in clunky drive; they have a delay between fwd/rev as they're relay-based.

The Botbitz 25a models should run a single drill each comfortably. But as mentioned their quality is questionable. We haven't had experience with the 25a model, but we are currently running the 85a model (could take 3 drills or something stupid happily!) and we are very impressed for the price. Great customer service too.

Links: www.electronize.co.uk and www.botbitz.com

Also don't worry about asking too many questions, as long as you're not asking which direction it is to tighten a screw we're happy to help.