I'd be curious to see how they work for you but my initial reaction to them is skeptical at best.
One: You're adding a whole of crap to your arrow. Good luck getting that thing to tune.
Two: Wouldn't the expanding barbs prevent a passthrough?
Three: What if you get a premature deployment? What if any of that stuff fails before, during, or after flight?
Four: Now you have an arrow that you can only use with these nocks because of the threaded insert... or am I missing something?
Five: Man i just don't like the look of these things...
If you're really looking to do more 'damage' just get a large DIA mechanical like grim reapers or rage. Both are proven in the field. Why chance it with something that looks ultra sketchy at best?
Just my .02 cents. Please report back after you have given them a whirl.
Regards,
d_rek