as a person trying to sell a GSR, seems like everyone wants a car bone stock. Those typically are the cars that were more cared for. Since the "riced" out cars typically are drove by teens who drive it hard. At least thats how it appears to my.
I myself never in a thousand years would by a car that was ever boosted unless i planned on a motor swap right away. Which i would also never buy a car with a swapped motor. I would rather do it myself, pay a little more but make sure its done right and will last.