New to the forum. I have not done anything with the plugs but I also get the hesitation with both the 91 and 93 tune from LMS as mentioned here. I got an email from LMS they blamed the winter blend of fuel. I was wondering for the guys with the hesitation did you have DTC stored? I had a few, I didn't write them down just cleared them when I tried the re-tune to 91 to see if it would help. I'm thinking something with the tune. BTW I have a 2014 non PP SHO running the V7 tune, Air Rais CAI and 170 Stat. Still waiting to hear back from LMS since swapping to 91 did not help.