John, I went with a Bell SR-Pro
I wanted an open face helmet for the comfort and fresh air...but being in an open car, I wanted more face protection ...so this is a little of both. There's nothing like sitting on a black-top grid with full sun on a 95 degree day in a full face helmet!!! HOT! HOT! HOT! The Visor on these helmets is very nice as it provides shade for your face. Do a search online....there are millions of mail order racer supply shops.
I'm very happy with my choice.