Well, I'll throw in my two cents. After owning/riding/researching/fixing one of these for 26 years now, my impressions are:
1) Handles okay, certainly not anywhere near many newer bikes. Handling can be improved greatly, and the items having the most impact seem to be (in no particular order):
a) Steering stem bearings
b) Swingarm bushings
c) Fork springs
d) Shocks
e) Tires
Ken at Cycle-X has dialed 'em in pretty good. They are scraping the heads off of the alternator cover bolts in the corners!
2) ALMOST everything appears to be available new or reproduction. The few hard parts that can't be found new can often be sourced used. Consumables are very reasonable and readily obtainable. The same holds true for many performance parts too.
3) 60,000 relatively trouble-free miles so far. Original engine. I find these very easy to work on.
4) Cylinder compression and exposure to the elements. Bikes that have been outdoors many years do not want to let loose of their fasteners (broken bolts when attempting disassembly will be in your future). IF it runs then excessive mechanical noises might give clues. These bikes have some chatter/clatter that may not be a problem, but if the noise is excessive, or is accompanied by banging/knocking sounds then there may be issues.
Forum members Hondaman, TwoTired, and others are way more knowledgeable the me, and Hondaman even wrote a book on them!