Well while it's certainly not "scientific" data, there were some interesting results when Box O Truth tested these awhile back...
http://www.theboxotruth.com/docs/bot23.htm
For those who dont wanna click thru, the "Lessons Learned":
Lessons learned:
The Extreme Shock ammo makes a couple of claims and we will look at the results. Please allow me to "paraphrase" some claims.
1. Claim: Their rounds are supposed to penetrate walls less than standard ammo.
Findings: The Fang Face penetrated 11 drywall boards, or over 5 interior walls without expanding or fragmenting. The Air Freedom round penetrated 4 boards, or 2 walls.
Less than a standard JHP round which penetrated all 12 boards, but still some penetration.
2. Claim: They are supposed to be able to penetrate a bad guy enough to be effective Stoppers.
Findings: Both the Fang Face and Air Freedom rounds only fully penetrated 1 jug and slightly entered the second jug.
This is equilivant of 3 or 4 inches of penetration in ballistic gelatin. Some experts have doubts that this is enough penetration to reach the vital organs of a bad guy.
3. Claim: They are advertised as worth their cost.
Finding: The cost for this ammo averaged about $1.85 per round, delivered. I see this as a big problem with "Specialty" ammo. We all know that it is very important to function test any carry ammo through your firearm. Who will or can afford to run 50 or 100 rounds of this stuff through a firearm to be sure it functions without a hitch?
Even if someone buys enough ammo to fill their magazine, it is unlikely that they will thoroughly test the functionality of the ammo.
I'm sure this ammo costs a lot to manufacture. Is it worth the cost? You be the judge. One thing for sure…..Shooting stuff is fun.
I think I'll just stick to the tried and true makers like Speer, Federal, etc.