WOW! Very surprised to hear what you say about the C3Pro!
I have the new Schuberth M1 (with communicator) and I like the fit and lower noise level and it is an OPEN FACE!
Not much time wearing it yet so my opinions are preliminary.
I checked in with my bro-in-law, who bought the C3Pro a few months ago just prior to me getting my M1.
He has quite a lot of miles wearing his and reports: Good helmet - fit is excellent - noise level a little better than his previous Scorpion - ventilation is excellent - chin strap fit is slightly problematic - fit & finish good. Overall he likes it. If he had a do-over, he would not spend the extra money over his previous Scorpion.