I have a 243 Browning A bolt with BOSS. I bought the rifle new in 1995. It is accurate and has never failed or had any problems.
Since I reload, the BOSS doesn't help or hurt the accuracy for me. Since recoil is not a problem for me with the .243, I use the non-ported BOSS tube to keep muzzle blast down. Recoil may be a concern with a 7mm Mag where the ported tube could be useful.
If you don't reload the BOSS may allow you to tune the harmonics for the factory loads you select. I reload and tune the loads for the rifle. I never adjust the BOSS.