I plan on keeping my white one forever. It was one of my dream cars I always wanted and i've pretty much built it my way and I cannot complain. Its repayed me by being a good solid car without any problems.
Black one, i'm not sure on it. Its been a good car too, if I can keep it around I will.
My TB SS ranks up there with my White GTP.
If I play my cards correctly, hopefully i'll eventully own most of my dreams cars, buy some land, build a nice house, and build a nice building to store my cars.....