Howdy folks.
I just thought this might be of interest (although it might be common knowledge already). Last night I was noticing how the core shape of the R9s is very similar to that of a 1911 and I figured I'd try it out in my high-quality Milt Sparks "Mirage" between-the-belt-and-the-pants slide for my 1911/Hi-Power. It worked very well. The gun is held tightly enough to not fall out when I do a summersault, but fairly springs into the hand on a draw. Since the holster is such a minimal leather slide, it's not oversized at all for the diminutive R9s.
Probably many of you already know this, but it appears that our 1911 belt slides will work just fine with the R9s.
cheers, erich