Older gun is equally as good if not better.
New guns have some MIM parts in them, trigger and hammer to name a few. Whether MIM parts are inferior to the cast earlier ones depends on who you talk to. I'll take the older non-MIM myself.
Older gun is probably smoother from shooting use, you won't have to put that first 1000 rounds or so through it or have a smith polish it up, trigger should be real nice already.
Of course it goes without saying inspect the gun for any possible problems, like timing and lockup, barrel and forcing cone wear. Problems like these are VERY rare on a Ruger but do occur.
Lastly, is the price right? If it is GO FOR IT.
Sal