Three single coil pickups give a nice range of tones. Each pickup can be switched on or off, so the combinations are whatever you want. (More than you get on a Strat.)The fourth switch is a bass cutoff switch. The fourth switch is more useful to guitarists than bassist IMHO. It is a cool guitar. Bass players may think you're stepping on their toes - unless they are playing even lower.
BTW, the red capo on a red guitar is a nice touch!