Had a riding buddy who had one. Actually, his may have been a '96. Can't remember for sure. He put 99gazillion miles on the bike with virtually no problems. The bike was bulletproof. He sold it, but the last we knew it was still going strong. We think your risks are low with the big KAW.
Same here - guy I used to work with had a mid 90's and he sold it with about 100k miles - ran into the guy he sold it to a few years later and it had 140k and still going strong. I don't think there are many known issue - you could probably do a search and find out what to be aware of for that model/yr.
One thing to watch on the late 90's VN1500's is that factory installed a plastic or nylon drive gear for the oil pump in the engine which sometimes failed, causing catastrophic engine failure. Replacement requires engine removal and, I think, splitting the cases. I think the factory responded and many of the plastic drive gears were replaced with steel drive gears, but not necessarily all of them.
Here are some links to topic threads regarding the plastic oil pump gear on the Vulcan website:
Apart from the plastic oil pump drive gear, the VN1500s have an excellent reputation for reliability. I missed a really good deal on one and am now kicking myself about it. I would suggest staying 2000 or newer to avoid the plastic oil pump gear problem and you'll then stand a good chance of having a highly reliable, nicely built machine...