Aerobats, Robins etc. will fly basic aeros but nothing requiring sustained inverted flight as they don't have the fuel and oil systems. Generally the flashier the machine the easier it is to fly aeros in them, so it's easier to learn aeros in a Pitts or CAP however it's not easier to fly them i.e. takeoff & landing, so you'll have to spend a bit of dosh to do that bit first. I suppose it comes down to moolah really; if you've got lots of it, go for the more capable machine (they're much more fun to fly as well).