Sorry, can't edit post on iPad easily, forgot to mention on set up it also depends on spring rates, OEM springs will be too soft so the car will roll more doling the car onto the outside of the tyres, this heats them up, drops their grip and wears them out.
Also be wary about buying part worns, most people have no idea how to look at a slick to determine its life, there are wear indicators but these are only indicative, most slicks lose about 30% of their grip after 5 heat cycles.
That said, I've got about 10 sets of part worns for CSL cup cars that happy to sell for £100 a set