Originally posted by mbratch
I've used the roller nut on my Strat for years. Tone and resonance has been excellent.
My gripe with them, though, is that there's a hard limit on string guage. You can't file them out to take larger guage strings if you want to exceed their normal maximum.
Not sure about how much effect it has on tuning stability. I haven't had tuning stability issues with the rollers. But, I think other factors might outweigh the effect of the nut as long as the strings you are using fit properly in whatever kind of nut you are using.