Although I like the concept and want them to work well, I don't think they will and I'll tell you why.
Last spring, I got the opportunity to take a ballistics workshop for my PD job put on by Vista Outdoors, the parent company of Speer, Federal and other companies. The instructor had tons of knowledge about ballistics, internal, external and terminal. The class was mostly about passing on knowledge about ballistic performance to assist in choosing effective duty ammo, but the same principals apply to CCW ammo. I already knew a bit of the info but learned quite a bit, as well.
When you are talking about bullets impacting at less then about 2200 FPS (which means practically any pistol bullet), the only thing the bullet does is punch a hole. There is no "hydrostatic effect" or anything else. It just punches a hole. Below 2200 FPS, you have not exceeded the elastic properties of human body tissues, so the bullet punches a hole, the tissues stretch out of the way, then snap back into place after the bullet passes. The tissue does not rip and tear, except for any tissue directly touched by the bullet. If the bullet has sharp edges on it, the edges may cut some tissue, but that is it. The bullet just punches a hole. The temporary cavity just snaps back into place with very little or no damage to it because you have not exceeded the elastic properties of the tissues.
When you get above 2200 FPS, things chance. Above 2200 FPS, you exceed the elastic limits of the body tissues and the temporary cavity starts ripping and tearing and you start to get damage outside the direct passage of the bullet. This is why rifle bullets are so damaging and effective, because they are traveling so fast that you exceed the elastic limits of the tissues and they cause a lot more damage than just the tissue directly touched by the bullet.
When you see damage in gel blocks caused by pistol bullets, keep in mind that the gel isn't as elastic as human tissue. The temporary cavities shown in gel blocks does not snap back into place like human tissues and is a representation of the pressure wave caused by the bullet. Because human tissues are more elastic, they will stretch but not rip and tear as shown in gel blocks, then simply snap back into place.
When talking about the Extreme Defense and Extreme Penetrator bullets, they do not exceed the 2200 FPS threshold, so they likely will not cause any more damage than a FMJ bullet. The cuts in the bullets will likely not do what they say they will because you have not exceeded the elastic properties of the tissues.
Having said all that, I applaud them for their ingenuity and attempt to make a more effective bullet. I hope they work the way they say they will because I really like the idea that the bullet is, basically, barrier blind and impervious to clogging when passing through heavy clothing. They should also punch through bone very well. I'll reserve judgement until there have been some shootings with these bullets and we have some definitive results as to how they perform in real life. I hope they will work the way they say they will, but I kinda doubt it because they are operating at handgun velocities that don't exceed the elastic limits of body tissues to be able to rip and tear like rifle bullets will. We'll see.
Bub75