I consistently ride in the desert heat all summer. Last summer was brutal, saw more 118 deg days in a month than I care to remember.
Used the multitec also. I also used a corsair for years before that. To this day I think the corsair is one of the best helmets known to man in several respects, venting included.
The multitec feels heavy sometimes. The vents are great but...I can't open the vents when it gets past about 113 anyways, lets way too much heat in.
I'm talking mostly about my K1200S riding regarding the full cov. On the LT, I used several depending on the trip, including the aria SZ-M (flip shield), which is really my fav but not a full cov. I find earplugs may not be needed all the time on the LT if the windsheild is adjusted just right with any of the choices.
Its hard to give up the utility of the shoei (especially if you like coffee
) but I'm thinking I'll go back to the corsair (a new one) when I'm ready to ride again, easier on a damaged neck I think. Still noisy, not sure you can get away from that with any helmet.
The SZ-M is the quietest on the LT in my opinion, but again, not a full cov.