Lumberjack, that sounds like a moral decision on your part. Do you think the roids will help your hand-eye coordination? Cuz, they won't. Do it, who the f*ck cares. If I have learned anything from davo2, its that your going to have to work harder and more efficient when on. I don't see that as cheating, if that's what you mean.
Also, you say you will both progress at the same rate, assuming your diets/training are in order, unless he gets hurt. Maybe this guy gets hurt then. Ya know, maybe two dudes beat the shit out of him somewhere outside of a bar. Who knows.
No, Just kidding, that would be cheating.
I also think its besides the point if this is how you make your money. Sure, its important to be the best, if its how you feed yourself. I also think it can be equally important, if its something you love/believe in as well.