I've used Tubb's bore finishing system on 2 rifles. I did this as a barrel break-in procedure so I can't say if it improved their accuracy or not. Both rifles shoot well. They do seem slightly easier to clean and foul less than my other rifles. It's not a huge difference, but it's noticeable. I wouldn't bother with it on a high-dollar, after-market barrel (or a Weatherby Mark V, which uses Krieger barrels, I think).