Eh. I'll give ya .221 Fireball ~equivalent, but that's about it. 'Course, it's been around forever so it can't possibly be whiz-bang enough for the marketing dept. I will say I'd just as soon NOT be in front of either of'em. Prolly had more to do with feeding, actually. But that's not nearly as much fun to pick about.
And it'll be ungodly loud, just like every other "varmint" type cartridge in a pistol-ish length barrel. Which will also decrease velocity. Unless they're using some new "special" .22 bullet, the smaller projectiles depend a lot on speed to perform. This coming from a varminting/reloading kinda guy who's ran a pretty wide spread of various .22 calibered cartridges (22LR to 22-250AI). But nothing really "tacticool". With the grumblings I hear/read about 5.56 penetration I find it a bit rich that decreasing the case capacity/velocity somehow a .22 bullet gets a big "S" on it's ogive and fixes that. The aforementioned velocities seem a bit optimistic from the reloading data I checked into on the quick. Either way, a specific bullet will have "x" type terminal ballistics @ "x" velocity no matter what it came out of. Beit a 5.7x28 from one of those funky l'il P90's or a .221 Fireball from a Thompson Contender.
But hey, mebbe 'ol Jake's off his rocker.
One of the regular posters over on ARfcom has a tagline.. "308, 'cause humans have a tendency to hide behind chit when ya start shootin at'em". I agree. d;^p
PS- I'm jest havin a l'il fun here. It's a sexy l'il cartridge just beggin to be necked up & down and initially gave me a l'il chubby just like the 6.8. I'm sure it's a hoot. I caught the same for my first 300BLK. I don't get a chance to fuss over ballistics much anymore. d;^)