Re: 250k Or 500k Pots with Single-Coil
It doesn't make a radical change, but the higher values give you a more pronounced resonant peak.
Pots , even "fancy" ones, are pretty cheap. If you're comfortable wiring your own guitars, it may make sense to just buy a set of each and try them both, and maybe record some clips to A/B to see which you prefer. It probably won't make a radical difference, though. The 250ks may sound a little thicker and meatier than the 500s, but it shouldn't be night and day.