Perry, One can only speak as one finds. On the M16 the air intake is on the induction side so will not be affected by heat. The water bottle is well away from the exhaust. The M16 can weep from the corner of the gasket but is a straight forward fix. I don't know if one is better than the other - they can both be tuned to give great rewards. MPG is the same I guess Mine will return 34 around town (an uprated version) and forty plus driving to Britain and back. See if you can try both. John and I obviously like them. Good luck.
