I'm running .030 or 35, I forget. I was running the larger gap because I know that it can act as a spark advance. I guess I'll go out tomorrow and tinker with it to see what feels good. My Grubee runs great at the current time. I'm thinking about getting an extended tip iridium plug. Haven't decided yet, KCvale seems to like them.So far the best thing I know to save them is keep your spark plug gap around 0.025".
I used to run 0.035" gap. It wasn't ever a problem till I got 2 Flying Horse 80 kits that run 8000 plus rpm. In every case when a coil failed it was during a long ride at very high rpm. I was also running a suppressor plug cap at the time, but I can't really say if or how much that may have contributed to the failure. Lets just say it didn't help anything.
After closing the gap to 0.025" I haven't lost a mag coil since, and I don't feel there was any decrease in performance either.