I bought a set of PT Night Sights for my P95. Although they were still sealed in the package, I sent them back to the manufacturer to have them refurbished and now they are guaranteed for life they told me. They are pretty cool but I don't think I will put them on my pistol. I'm going to CCW the 345 instead. So I'm not much help huh? LOL
I can't speak to night sights from personal experience, but this is a summary of the many opinions of those who have tried them:
If it is dark enough for the night sight to be significantly more visible than a good "low light" sight, then it is dark enough for the muzzle flash from the first round to wipe out your night vision to the point that the sights will no longer be visible.
If low light marksmanship is your goal, you probably should also investigate one of the better laser aiming systems such as Crimsom Trace--and learning to make that first shot count.
I'd like to hear input from those who have actual night-time firing experience (no, one or two trips to a well-lighted range doesn't count).