I have now sent two slides to Vulcan and I have been very impressed. They send you an email when the slide arrives to say "your slide is in house and in the cue". Then when finished, they send a message saying "your slide is coming back home". They drilled both my Sig P226's , one with RMR and another with Holosun. Both came out very nice. My initial problem was I stripped the screws they sent and used another screw that bottomed out, according to them. But they installed for me and its perfect. Expensive but quality work.
PB