I can vouch for the comfort and quality of the Z1R brand of helmets, I even found one that matches the bike! my wife has a Scorpion brand Scorpion model, very high quality helmet!!!! the best graphics I have seen short of a Suomy too. We also have the HJC modular helmets that we wear when riding 2 up on the V2K, a good helmet no frills and a bit noisy in my opinion but I believe it is from the modular design so I hear. I intend to buy a nice Suomy or Scorpion with a killer graphics job someday soon, As for reflective tape and decals, I doubt they can in any way adversly effect the helmets integrity. Try
PurpleHarley_Decals_Stickers for reflective stickers for helmets.