I would like to know if I need it right away for performance reasons or it not a big deal

Also im stock 00 z28/ss

 

you most likely will not have to upgrade your stock driveshaft for a while. first off is it auto or 6spd?

if you are using your car at the track a lot and are actually hooking. it could be an issue depending on the power output of your car. being stock i doubt you will have an issue

 

I've seen people with manual transmissions break them when out banging gears on the street. If it's an automatic you should be good for now. Bob