If it truly is an “A” then it has had the spar mods done and is back to being aerobatic. The “B” has a completely different wing and doesn’t require as much research to be sure you know what you’re getting. Nothing wrong with the “A” but you need to really understand what that particular airplane has for wings. If it hasn’t had the mods then it’s a straight 3 and is limited to 4.4 G, must have a placard prohibiting aerobatics, and must have a G meter so you can ensure you don’t get too rambunctious.
Just research what you’re getting so you know in advance. Multiple rivit sizes and patterns used on the spar, glued or unglued skins, and fuel tank locations. First mod involved the rear spar attach and inner rib stiffening; second one was for stiffeners on the main spar webs between ribs to prevent bowing.