OK, I'm intrigued by this process, but I'm not seeing much posted here by people who have actually spent the long green to have it done and used it a lot. Is it "worth it"? Subjectively or objectively, how much did it tighten groups or reduce recoil? How much does the porting lessen velocity? Does it make 590 barrels any harder to clean or oil? In my case, I picked a Mariner decades ago because I needed a good finish for saltwater environments. It's held up great. Now I'm looking at paying someone a lot of money to drill a bunch of tiny holes through that finish? What does Vang do to protect the bare steel this drilling and the backboring exposes? Does Mossberg approve or disapprove of the Vang processes? Not trying to be snarky, just want honest user reports. Thanks!