100cc would bring out better flying characteristics of basically any scale aerobatic plane,especially when it come to IMAC/pattern and 3D planes ...imo 100cc is the biggest i would go personally and 50cc on up is where they really start to shine....after 100cc they almost double in price and become a pain in the @ass to transport...

bigger flys better in most cases... with the exception of a stick.... i like the maneuverability of a 40 size stick, but flew a giant gasser stick and it was a totally different animal, too tame for me.