At what point can you tell it is time to replace the shocks on your quad. My stock shocks on the Z are starting to get a little soft.

 

When you can afford new ones.....
Are they leaking any fluid?
As new as the Z's are, without blowing one, I would assume that they still have life. I know that the next mod for my wifes is some new boingers, set up for a 100 pounder, she is like a rag doll on it. I have them set all the was soft.