I find that with less expensive and budget guitars, the pickup installation drastically affects tone, as will saddle and nut material and fit, general set-up (including relief), assembly (loose machine heads, neck fit, etc), and string quality. Other things like fret dressing and intonation make anything more playable. Why these things aren't a matter of quality control at the factory is likely a function of price. Besides that, vendors can't be trusted to address the issue either.

Be that as it may, those strident, shrill, grating trebles I hear in the cheap guitars just about drive me insane. It seems they either have that quality or the treble is almost nonexistent. For the purpose of listening to students at lessons, I prefer the latter to the former.

ESP does market some nice electric stuff (though not generally old school enough for me), but I don't know how much of their catalogue they actually manufacture or whether much of it is contracted out.

Peace, Mooh.