Good information provided above. For an interesting read, Charlie Kelsey's bio is good material.
Paris Theodore was a contemporary of Kelsey. Though I have not handled a Devel, I did covetously handle an ASP by Theodore at a Knoxville gun show. I was $200 behind on the owner's asking price and did not think I would shoot or carry it. I passed on it. Wish I had the chance at one today.