z06 or cobra are not downgrades. i don't care how fast the notch is in a straight line, its a 17 year old car, period. as far as overall worth, z-06>cobra>notch.
don't get me wrong, i love foxes, but drive a cobra or z, and you'll be sold. i'd keep the fox, and buy the cobra or z. you will NEVER get the $$$ that the notch is worth to you-unfortunately.
none of the 3 mentioned make good daily drivers. GTO's, on the other hand, make fantastic daily drivers