I used Doug at ATEi to do an install of a RMR on my G19 along with a Tenifer recoat of the slide, also suppressor height sights. 100% satisfied with the work. Would use him again in a heartbeat. I used Primary Machine to do a slide mill, cerikote, and sup height sights install on my G34. Used Primary Machine this time because I was going with a DP Pro red dot. Again, 100% satisfied with the work. would also use PM again without thinking twice. On both jobs the slide work was flawless, slide coating ditto. ATEi was a little more price-wise when comparing shops that would do the milling for an RMR. Then again, Doug DOES more work to the slide for correct installation that others take the easy way out and charge less. A person that I know paid some big bucks for a big name RMR slide for his G19. RMR fell off on about the 3rd mag through the gun. Why? Mounting slot was too long and no stabilizing lugs. You get what you pay for.