Here's my thread over on specialty pistols on bedding the xp-100r stock.
Login To: Specialty Pistols
I bought a $50 brake from the Ross guy in Mountain Home Idaho and had my gunsmith fit it to my .223 for a total of $200 for the project. I don't like the muzzle flip of these guns so prefer to brake them.
My paint was Brownells aluma-hyde2, then the Krylon craft store web then several top coats with the Brownells matt clear aluma-hyde2.
Were I to paint it again I'd just send it off to a pro composite stock painter. The krylon product is incredibly difficult to get a satisfactory result with.