If you are an "attention to detail" type of person it's pretty easy to do. Prep is everything and if you're willing to take your time taping things off and ensuring the parts are free of oil, grease & dirt then it should turn out fine. The actual spraying of the stuff is nothing difficult though it might not be a bad idea to try it on something other than a gun first to get the feel for it.
If you can follow directions and make sure that you clean your parts with what Duracoat recommends, you'll be fine. In doing close to 50 I have never had a problem. Only time I have seen an issue is when another INGOer had their Kimber done, incorrectly. We stripped the bad Duracoat off and refinished the piece.