for me huge benefits POWER steering , Infinity q45 brakes and s13 HKS coilovers, you can use almost any brake system that we can use on a 240sx, this car now drives , stops , Handles like a newer car, I only want it this for racing, and autocross
here is a small list of suspension and Brakes parts:
S12 Crossmember
S13 control arms
s13 Kazama tension Rods
S13 Tein Super Drift coilovers
280zx rear disc brakes
Q45 front calipers
Z32 front rotors
S13 spindles