The model 85 from the late 80's/early 90's is a good, sturdy gun that in most cases is very reliable.
There is indeed a lot of ambiguity as to the +P rating for these earlier revolvers. The best you're really going to get is, that a light diet of +P through these revolvers should be fine, but stick to the regular pressure ammo for most shooting. What I would do is, practice with regular ammo, then run one cylinder full of +P through it so I had a feel for what recoil would be like. Then, when carrying it, I would load it with the +P.
You should give your revolver a good going over to be sure that there are no excessive wear signs. What I said above is for a revolver that is in good shape. If in doubt, just use standard pressure ammo. They've come a long way with hollowpoint ammo these days.