$32, that's about £20 plus shipping for a 35V 2.5A stepper driver. You can get 50V, 4.2A stepper drivers for about £25 including shipping, less if you buy a few at a time. I'd spend the extra £5.

Also, I find it worrying that the voltage and current ratings you specified are simply the 'absolute maximum' ratings taken from the datasheet. The absolute maximum ratings are just that, they're not the parameters you should be running the device at. In reality the voltage rating should be lowered to account for back emf from the stepper motors, and the current rating will be less then 2.5A since you don't appear to have any heatsinks on the driver ICs.