Depends on what bore you use. IMO, the best thing you could possibly do for a barrel is get it freak bored, that way you have the aesthetics that match your marker and you get the freak bore options.
It won't be a game changing difference, but you might notice a quieter shot and depending on how OCD you are about air more shots.
You may call it fat, I call it bounce padding.
Dynamic broke meter (relevant when adding when trading): Moderate - I could add in the range of $20