Suspension Bushing advice

[Ray Sta.Juana]

I currently have 101500 miles on my car and I've been contemplating about
wether it's time to replace the bushings on my car. Is there any mileage
guidelines or is it based on time? I've had the car brand new since Sep 98
so it hasn't been too long has it? It's probably gonna be one of those mods
that you don't know how bad the bushings are till u replace them isn't it?
Anyways, I have a few more questions about some suspension setups that I'm
looking into but I'll save that for later. Thanx in advance.

Ray S
98 Sentra SE