First Thanks to everyone and their input be it Good, Bad or indifferent on the M8 though this very informative thread.
I haven't had any summing issues,(knock on wood) and Lord knows I'm not easy on my 17 CVO SG, however I usually only ride short distances (less than 1- 2 hrs.) and only about 4K mi in 13 months.
This, only my 2nd Harley, is the most responsive (and expensive) bike I've ever owned or ridden.
We just went through a week of 90+ degree weather last week, I noticed at stop lights the engine would labor especially if dropping one cylinder due to heat, but it acted like it wanted to stall. After I revd 3-times and 2nd cylinder started back up but it still acted like it wanted to stall.
Taking off from the light the bike was little sluggish, a little more heat than usual......Obviously. however the bike wasn't as spunky as usual.

not issues since that one day.
Anyway to test the bike for summing or I'll know it when it happens.