I recall the prior night sight thread, and yes, the R9s owner who had them installed had multiple vials break very quickly during practice.
I also recall a more recent thread wherein the R9 was compared to the NAA G380, with someone who owns both saying that the Rohrbaugh has less felt recoil. The tritium on my G380 holds up generally no worse than other night sights I have had.
I wonder to what extent felt recoil translates into the way recoil affects something attached to the slide, especially since we are comparing a straight blowback to a tilt barrel? If they do compare, maybe tritium is feasible.
I certainly hope it is, as I have regarded tritium is a near-necessity since I got my first pair of such sights.