I do not like Freak. To expensive, to complycated. Silly, weak, tiny inserts. To many places for dirt or inaccuracies. Imho is a lot better to have two or three good inepiece barrels with different internal diametres, or something like Empire barrel kit with full-sized barrel backs.
But If you can choose your own paint (FPO limits), there is no need of these toys. Simply get one good barrel with medium bore diameter and good paint for it.