Once and never again. I was young and excited when I bought a NSRT-4 and the dealer wouldn't let me test drive it. I quickly found out why when it overboosted and the turbo decided to quit. It was modded and the dealer had no idea what was done but they clearly knew something wasn't quite right or else why not let me test drive? After that I discovered a slew of other, smaller issues but it was enough to deter me from doing it again.