So I bought a Sugino RD crankset. You know. Like everyone else, because they are cheap, and the place sent me a Sugino RD 5000 Direct Drive. Now this crankset is indended for mountainbike use, but also costs 100 dollars more than the one I bought. I know the right thing to do would be to inform the company of its error, but they pissed me off, backordering something without telling me, sending me the wrong products, and on top of that it took 3 weeks to get.

Anyways. The question:

Is there a huge difference in mountain bike and single speed cranksets? Can I just throw a 44t chainring on it, and everything should be fine, or would it be advised to get a dedicated single speed crank?