If it's a good shoot, it's a good shoot. But I think shooter is right, in this day and age it's all about public perception. Especially if it came down to a civil case.
Two other cons;
1. Availabilty and Price:
http://www.oathammo.com/tango-shotgun-round Sorry, but almost $10 a shell? I haven't bought any in a couple of years, but I recall the low recoil Hornady 00 Buck shells I bought were about $1 each. $45 buys a very nice mix of buck and slugs for just about any defensive scenario I can think of.
2. I'm not impressed by the gel tests I found. Only 10" of penetration? I'm a fan of putting holes through vitals. I'd be very concerned about reaching those vitals to produce a stop. They went for massive expansion over penetration. It also wouldn't surprise me to find out shooting through heavy clothing causes premature expansion and penetration depth is even lower.