Thats a Tom Mcguire controller. Good design for bare basic driver, no frills, no bells, no 1/4 step 1/2 step etc. Will carry fare amount of current. I built one for 3x motors, works fine. Have drawn slightly over 3 amps when all motors turning.
In order to get speed, bells etc you will need to move up to geko, or hobby-cnc etc chopper type controller .Good for proof of concept, fun build. Go back and reread doc to find max current cap for FETs. Can't remember off hand but it's up there a bit. Hope this helps.