I have tried shooting brass that was deburred & not deburred. If there was a difference I can't tell it. I'm not a competitive shooter, a hunter. I get consistent accuracy from my reloads as the case comes. I also don't sort by weight. A receint group shot by my Savage 260 Rem & Badlands Precision 6.5 125gr. Rem brass as it comes out of the bag at random. No sorting, no deburring. Three shots at 110yds.
Attachment 286044 This group was shot yesterday after sighting in. Ammo was loaded with Lee brand dies with a "collet" neck sizer. Just about zero run out. I see this as being far more important than deburring.