CountZero,
I don't have an R9 Robar, but I do have the Robar NP3+ finish on my H&K P7, and I can tell you it's extremely tough and wear-resistant, not to mention it's very slick, so it's easy to wipe surfaces clean with little effort. I've had the finish for a year now, and so far, repeated insertion and drawing from my holster has produced negligible holster wear; only a slight polishing of the NP3+ surface on the upper edge of the left side slide flat. There is very little wear on the slide and frame tracks as well, after about 1000 rounds fired. The visible "wear" isn't through the finish; it's only surface polishing. NP3+ also has self-lubricating properties, so less lubrication is required between mating parts. As a bonus, I think the soft silver-gray appearance looks good too.
The only disadvantage to NP3+ is is pretty expensive compared to other finishes, but I think it's worth it, and I highly recommend it.