I have a couple of Shoei’s which fit me perfectly, no hot spots or anything. I got a c3 pro earlier this year. Tried it on briefly, all good. Went for a ride after I got it, and after a while it just wrecked my forehead. Just not for me. I’m told the c4 is a different shape? If you find something that works, I’d be inclined to stay with it. Good Luck.