I've changed tunings a lot of times on my basses and have never had tuning stability problems using a nut that actually will fit up to a .185 on the lowest string. As long as the tuning pegs on the headstock line up nicely with the slots on the nut it should be a non-issue. Same with truss rod. There is little or no difference in tension between an equivalent set with one or the other. The only caveat is needing to raise the low string barrel when using a tapercore string. And of course intonation, which takes only a couple minutes.