M2 are the softer compound tires. We run on a blue-groove track and with 3 qualifers and 15 minute mains i use a set a day. On the bigger races with 45 minute - 1 hour mains i usually go through 2 sets a day. With the XTR compound it takes about 2-3 race days to wear them out and the difference in traction is hardly noticeable with a harder compound.

If you are running on a hard track like blue groove run some Knuckles, they last long and hook up great.

Steve