How do you know a design is good?

When everyone and their hairdresser is ripping off your invention as soon as the patent is expired.  I only just realized not too long ago that Benelli's inertia system patent had expired back in '06.  This in itself is somewhat interesting, but what gets me, is watching the all the shotgun makers of the world immediately start making inertia *cough!* Benelli wanna-be*cough!* systems of their own.  I have a feeling that in the coming months and years, that just about all the major gun manufacturers will be spewing forth "inertia driven" systems like a twisted rerun of The Exorcist made for the Bradys.

The Marocci SI 12

The Firearm Blog has already noted two that have come out so far, the Marocci SI 12, and the newer Browning A5.  Considering that it's been over five years since that patent expired, I'm sure any other companies with a mind to produce an 'inertia gun' are either finishing up their R&D on a new line of guns, or may end up just jumping on the bandwagon towards making one, if the marked proves good for them.

As for these guns already released, I think they are pretty cool, but I find it a bit of an annoyance when Browning insists on styling a brand new system on a 100 year old gun, which actually has absolutely nothing in common with the new gun other than a similar name.  Just my opinion, but wouldn't ripping off someone else's design, to make a gun to succeed one of Browning's originals by giving it the nickname to the original weapon, and styling the receiver in the shape of the old one, kind of a little bit insulting to the big J.M.B.?

The ridiculous (if not misleading) Browning A5