When my son moved up from the TTR he went to a 99 YZ 125. It was rock solid. It was light, turned on a dime. It was a well designed bike. I sold it to a buddy who still rides it. I always maintained the bikes, but now its lucky if it gets a bath once a year. The only things he's done to it is replace the shifter (the splines in the shifter were worn), and he did the rings once in the 3 years he's had it. I say its been pretty solid. I've ridden with other who had the same vintage bike, and only one had a problem. They waited too long to to the top end, and the cylinder needed sleeved. So they went with a new athena cylinder and head.
I sold the 99 YZ 3 years ago for $1,300. I was asking $1,500 but I knew all he could afford was $1,300. I've known him for over 20 years, so I didn't get the money I wanted, but I gained a new riding buddy.
Coop I live West of Pittsburgh and I think you are East of the city. If you find a bike West side of the city, let me know. If I'm available, I'll be happy to check it over for you, so you don't waste a trip on a clapped out bike.
Eric