In Mexico, we were quite happy with sight-mount.com. Suppressors are legal in Mexico. So many people who have a decent pistol (most don't) sometimes think about a suppressor. It's sort of fun blasting down multiple pepper poppers and the
clang from the bullet impacts is louder than the shots.
Iron sights often don't really clear the suppressor and when they do, they are tall and uber-ugly. At least, to me. Red Dot's can get you a point to aim at that clears the suppressor.
The sight-mount sight requires a hole to be drilled and tapped -- at least on the Glock (I'm tempted to put one on my own Beretta 92fs here in Canada). Oh, and you have to order the particular mount for the style of pistol you are using. They make them for Glocks, Berettas, Sigs, 1911's and just about everything else I think. At the time I took these photos I did not yet have the stabilizing hole drilled into my slide and yet everything worked great anyway.
The sight-mount mount allows you to have nice (fixed) iron sights, that allow you to instantly install your Red Dot on top of. I liked the set-up very much. I did it on my own Glock, which I never did suppress, but after I experimented with the sight-mount sight several others of my friends did buy one for guns they were suppressing.
Certainly, at the time, it was a nice set-up. When I get back to Mexico on a more fulltime basis I probably won't go down the Glock road. I think I'll do the Beretta 92fs thing. The one I have here in Canada is decent, and I'm working on some customizations (G-Model safety, Short trigger, some frame dehorning etc.) that make the gun more comfortable for me so I'll probably look for one down there as well and customize the two equally. And the sight-mount sight system is definitely something I'm considering getting for my Beretta up here as well. I've added the photos I have of the one that was on our Mexican Glock so you can check it out.