Most of the DSM's are put away for the winter. Next spring there should be a dyno day, that would be a good time to head down. That guy is full of shit if he says he has 600hp and runs a 127 mph trap. That might be 400 awhp. I grew up in a smaller town and everyone guessed at hp. Add up the claims by the manufacturer, and you get hp, right?
If it hasn't put it down on a dyno, then it hasn't done it.