Don't mix brands, if you can avoid it. Krylon and RustOleum, especially, don't play well together. If you must for some reason (shouldn't be an issue with this helmet), allow the first one to completely cure (get right down to it and if it smells even faintly like paint, it's not there yet) before applying the second. Gloss takes longer to cure than flat.
Personally I was mixed about the DP helmet when it came out. Too many of their helmets are undersized, due to mold shrinkage. Their Biker Scout and Royal Guard are, IMO, the worst offenders, in that respect. I can barely get the DP past my cheekbones, and resting flat on my head the shoulder flares are hanging in the air several inches above my shoulders. And I'm 6'1" of average build. The Rubies Supreme edition is so dead-on to the originals (but fiberglass versus vac-formed plastic glued together, as the originals were) I almost wept I was so happy. Pricey, but sooooo worth it. So I'd ask what your build is, size of your head, etc. And even then there were things I was working on fixing on the DP prior to it instantly being shoved aside when I got the Rubies. *heh*
--Jonah