Let's put it this way... if I bought OEM rotors from the dealer they would cost the following...

Front: Part # 5135475AA $92 Each ($184 a pair)
Rear: Part # 5135505AA $60 Each ($120 a pair)

Now... to have the cross drilling, slotting and cryo done by Porterfield was going to be $94 per rotor. This works out to an additional $188 per pair... now the pricing looks like this.

Front: $184 + $188 = $372
Rear: $120 + $188 = $308

Total: $680

This would also take time and cost more shipping as I would have to procure the rotors... ship them to Porterfield, wait for the work to be done and then they would probably charge me shipping in return.

All told, I think it's just about a wash.

I probably will have my old rotors slotted by Porterfield and use them just for the track... I haven't decided yet.