nitrous newbie questions.

How old/used is this kit?

It was on a nova for about 5yrs, sat for 6months then I got the plate and solenoids and got my own bottle, I tested the noids and everything works, hooked the n20 solenoid to a full bottle and it didn't leak any through. I have to get a new feed line though, ine got pinched and sprung a leak.