For a street rig, go limited slip - won't wear out your tires or make noise on dry pavement, will act as a posi off road, where it counts.
You can go clutch based (trak-loc, powerk-lok, etc etc) or helical based (tru-track - gear type, nothing to wear out)
I've got l/s front and rear in my pickup and with the front locked in and turning in the parking lot the truck will noticeable slow down and bind up, power-loks work awesome.