Pumpkins are not people; they're not a close analogue for human tissue. You can spend a crapload of money on that stuff if you want, but it's not going to disable an attacker any more effectively than a name-brand defensive load; if you truly believe that RIP ammo will accomplish anything more than conventional hollowpoint ammunition will, I don't think your really understand how pistol cartridges work. You can't pack a whole lot of energy into an object half the size of a AA battery, regardless of the projectile's configuration.
I've heard the "inside Joke" was that SXT really meant Same Exact Thing.:thumbupFirst of all, Black Talon ammunition was never banned; Winchester voluntarily withdrew it from the market due to all the negative media attention. Winchester SXT ammunition is essentially the same design.
Second, the general consensus among the firearms community is that RIP ammo is a gimmick, and it is not likely to outperform other conventional modern hollowpoint designs.
YupWeight retention, expansion and penetration are what you want in a man-stopper. This has none of those characteristics. There is no better way to stop a threat than shot placement. Anything short of a CNS hit will not kill someone instantly