if you don't use good fitting plugs you WILL damage your hearing - and it's irreversible.anything above a 30 limit and I'll wear mine. I use the orange Max ones, bought a box of 100 of ebay. Ive always had problems fitting one in my right ear and over the years have developed tinitus in that ear. actually depresses me sometimes when I'm lying in bed and it's quiet and all I can "hear" is the two tone ringing in my ear. wished I'd take more care.tried the custom plugs a few years ago from the Scottish Bike Show - were OK until I tried them on my bike - hadn't been fitted correctly cos my lid pushed my ear back further than it was at the fitting. so they're useless on the bike. next helmet might be a schuberth (had AGV Q3 - good, Xlite 801 - ok, Shoei XR1000 - ok)like eddie, I take them to gigs too.
Ive always had problems fitting one in my right ear