Shall I assume that as you didn't try to talk me out of it, the Pitts isn't such a bad idea?
Well, it has its advantages and disadvantages.
You'll need to learn to taxi, takeoff and land. If you haven't flown a taildragger before, this will take a bit of time, and the Pitts isn't the best taildragger for learning on. It takes off very quickly, and it's hard to feel what's happening. It has powerful controls, so you can overcontrol it if you're not careful. And it has poor visibility (although from the back seat of an S2 it's not too bad). Having said that, it was the first tailwheel type I flew apart from some low powered motor gliders, and after a few horrendous takeoffs and landings where I lived only thanks to the instructor's quick reactions, it wasn't too bad. You should expect to spend quite a few hours in the circuit if you want to solo it.
The next downside is that it isn't a terribly good classroom. The instructor is in front of you (probably behind you actually for the first few flights), and it's a noisy, cold, drafty aeroplane. Alan Cassidy's S2A has a canopy over both front and back cockpits, so it may not be quite as cold and windy as the one I flew.
When it comes to aeros, some manouvers are easy (rolls), others are quite hard to get right. The Pitts will bite you when some other aeroplanes won't. I'm not sure if that's a good thing or a bad thing.... As an example, you can do a nice entry into an inverted spin from a botched stall turn, and I went through a phase of doing uninentional inverted flicks when rolling off the top of a loop.
Like any aerobatic aeroplane, you need to fly with finesse to get the best out of it. However, some low-powered slow-rolling types need finesse to get anything out of them at all, and that's a good way to learn.
The Pitts has the advantage that you can let things go a bit wrong safely. You can also do inverted spins in it, which isn't the case with most aircraft used for aeros training in the UK.
In conclusion, I'd say that it wouldn't be the aeroplane that I'd recommend for initial aerobatics training, but given the choice between a Cessna at £141, a Cap at £185 and a Pitts at £200, I'd probably go for the Pitts at the moment. If the Cap was given its +6g limit back, I'd go for that instead.
But you should consider moving somewhere cheaper!
Regardless of all that, though, I think that anyone who gets the opportunity to fly a Pitts should take it. One of the most satisfying things I've ever done was my first perfect landing in a Pitts.
(Needless to say, it got me back later....
)