How will these sound on a Spider III 75 amp?
Are these pick-ups meant for a solid state amp or a tube amp?

Oh lord, here we go again. So heres the deal, you dont need new pickups, you need a new amplifier. Once you get yourself a nice amp feel free to spend money on pickups. About the p-ups being made for solid-state or tube amps: The way I see it any kind of guitar with any kind of pickup sounds better with tube. Solid-states just dont sound as good, no matter what guitar you're playing with.