The Centurion V2 uses a milspec barrel extension, The Centurion E4 uses a KAC barrel extension. The Centurion is also much cheaper than an E-bolt ($380 from anyone who isn't LMT) or even a Geissele Stressproof ($250 vs $125 and comes with dual ejectors). This doesn't mean that the V2 is even say, 80% as good as either of them in any given metric (lifespan of the bolt itself, extraction, ejection) but it clearly means you can get 3 V2's for the price of 1 E-bolt. Whether that's a good deal will require several years of testing and tens of thousands of rounds by maybe a dozen different people.
Yeahhuh!
Only if you're a weakling.
Is Chuck Pressburg a weakling? (Admittedly his primary intent in attaching the KKM comp to the original Roland Special was keeping carbon off the lense of his X300 but a flatter shooting gun was a noted and measurable side effect, which indicates that there is a level of mechanical advantage in performance that can complement and improve upon pure physiological performance).
proper grip with enough strength to properly control recoil.
As Aaron Cowan has (essentially) said, there is no Blue Ribbon for being a big tough strong man who only ever shoots +P++, Firearms should not have recoil nor muzzle flip, the only reason they do is the laws of physics and practical considerations.
The ever increasing amount of factory comped handguns produced by a variety of manufacturers (Sig, S&W, FN, Springfield, Shadow Systems) and aftermarket recoil reduction solutions (PMM, Radian, Agency Arms, Rogue Gun works Alpha 6, Shalotek, Fdez werx and many more) indicates to me that the defensive pistol industry has reached the next step in handgun evolution. First there were light rails, then MRDS mounts and soon Compensation