I have used it on several guns. A G23, 1911, Rem 870, and a dept issue MP5.
The finish has held up very good. I carry the G23 all the time and have not had any problems. There is no issues with the long guns either.
It is easy to apply. The hardest thing is cleaning the guns. Use their cleaning products to strip the oil from your gun. Also take your time when you tape off what you dont want painted.
Good luck