It's a 1976 airplane, built from a factory kit and certified as an experimental homebuilt. It was stripped to the skeleton and refurbished in 1991. I did lots of homework in the process of buying this airplane, some evidence of which you can see in prior threads on this board.In the course of my airplane search, I eventually compiled a pretty standard list of initial questions. By the end, I was able to ask questions that helped me quickly reject a lot of airplanes that looked good in the ads.
So with the airplane I ended up buying, I'd I asked the by-then standard one ton of questions to start, along with looking at a couple dozen pictures the seller sent me. Then I scouted for a local Pitts expert to do a detailed pre-purchase inspection. That inspection cost me some money, but it was well worth it in the assurance that I was making a good buying decision. Finally, after pretty much deciding I'd make the purchase, I went to look at the airplane for myself, ask the seller another ton of questions, and learn from him some of the particular personality quirks of the airplane.
S-2As and Bs are fine airplanes, if you are sure you really need a two-place. To rephrase a point that Kendal alluded to, I think many people would say that an S-1T can perform better than either an S-2A or S-2B, on less gas. Beware of seeming bargains with run-out engines. For a Pitts, 800 or 900 hours SMOH is a lot of time, and not long until the next major overhaul is needed. A major engine overhaul for a 4-cylinder Pitts can cost $15K to $25K, and I'm sure it's a lot more for a 6-cylinder.
Hope this helps!
Tom P.