I have (sort of) the same problem but with the Extra. I live in Europe and fly Airbuses for a living. Ever since my first aerobatic session during flight training in Phoenix (about 4 years ago), I immediately fell in love with aerobatics. At the time we were training in a C152 Aerobat. Not too fancy, but an excellent training tool before moving on.
As I'm from Belgium (that's an itsy pitsy teenie weenie country) opportunities for aerobatic flying are limited to say the least. 3 years ago I met a guy (one of my best friends now) who owns a lot of aircraft, among which a beautifully maintained Pitts S-2A. Strange but true: he isn't even checked out on it.
I checked out on his Pitts after 4 hours (in retrospect, no one should ever fly a Pitts after only 4 hours) and have about 80 hours on it by now, largely aerobatics. I try to take up passengers to reduce the cost as much as possible.
My 2 cents: try to find a Pitts for an introductory flight. If you like it (which I'm sure you will) then find one to rent before purchasing. Flying a Pitts is demanding but rewarding at the same time.
And always get professional instruction before trying out aerobatic figures yourself (I'm sure you know this already, but I learned that the hard way). A Pitts is notorious for its spin characteristics, as Patty suggested. After some instruction and practise you'll find it no harder to spin the Pitts than any other aerobatic plane.
Now my friend is thinking of buying an Extra 300. Although I've never flown it, I'm sure it must be an exciting rig. Problem is that I feel like I haven't explored all the possibilities of the Pitts. It's like an extension of my body whenever I'm in it. What I'm trying to say is: the Pitts will keep you busy for a long, long time.
The Pitts is an excellent choice and you'll quickly fall in love with it, guaranteed.
Just beware of the pitfalls of (co-)ownership. Be sure to have sufficient demand to keep it in the air as much as possible and make good, solid agreements with this other guy.
(Sorry for my English, it's not my mother tongue.)
And Patty: I'm reading your biography 'Fire and Air' and I love it! It keeps me company on those long flights. I had great respect for you before, but that has increased tenfold by now. Happy flying !