I've ran M1,3,and 5. On the dyno, and at the track. The M5 is better all the way around. No need for top lube, easier starting, wider tuning range, and more power. Was worth on average, 5 percent more power. Ran it with the same jetting as M1, and then jetted up, didn't hurt anything with same jetting, but did pick up with jetting, and timing. My feeling is, it just atomizes better than straight meth, so you can burn more of it than M1 in the same scenario.