I would say a 692.
I use a freak barrel, but have only used the 693 insert for the last god knows how many months. I play up front and dont need to have the best consistency (although my ion is damn consistant ) or pin point accuracy every single ball.
If you get a 692, it should fit most the balls you should shoot, as in they wont be too big to not fit and cause excessive breaking.
Depends on the paint, but if u are varying the type of paint u use, i would go for the biggest one, that will fit all sizes of paint and cut out the possibility of barrel breaks.