Just got back from Victor's. He did deep laser engraving over a very shallow engraving that was already there. Took a lot of time to line it up just right so the old wouldn't show. Also had to do it on both sides (different sizes). He was super patient and got almost perfect match.
I took so long that 4 other calgunners showed up after me. If you're engraving a blank lower, I'd guess it takes no more than 30 minutes tops for all the graphics, text, markings per lower. Just send him the artwork ahead of time. he said .svg files work best, but I sent him .jpg and it was fine.
Suggest stripping your lower, or at least remove buffer tube before you get there.
