i'm about to get a 1983 trek 500. it has all the original suntour parts. suntour vx rear derailleur and ar front derailleur and super custom cranks. the frame and fork are in great condition and im keeping this since i finally found a steel trek that fits me. whats your opinions on these components? should they be upgraded? i have a nice dura ace crankset on another trek im selling, i thought about swapping the cranks and upgrading the derailleurs.and this is a prime canidate for a brooks saddle.