when it comes to barrels you need to match the barrel with the paint you shooting on the day and the best way to do this is with a barrel set, something like a Freak set or a Evil Pipe Kit
If you go out and buy a .89 barrel and the paint you shooting is .92 then you going to get a lot of ball breaking in the barrel. By getting a barrel set like a freak or a Pipe kit you can then match the balls with the back part of the barrel set with the balls you shooting this also helps with the vertical of the marker also.