While I don't have any measurement info... the LPO floating rotors on my 2SS are very thick, I was surprised when I took the wheel off and looked at them.
A good set of floating rotors and 6 piston calipers will not be significantly cheaper. I upgraded to floating rotors for my CTS-V1; a pair of 14" rotors (non Brembo) were $1,200... and they were definitely thinner than the ones on my 2SS.
If you just want the look and some performance increase - then a pair of floating rotors in the stock size (for the 4 piston system) and some red caliper paint will do the trick
