Damn sharp and powerful unit. Range instructor had one at the range last summer. They are kick ass. If I ever have an extra $1300 to blow, I will definitely consider picking one up.
Love them crossbows and one that will fit to your AR lower, hell that's great combination adaptability. Was shooting 1 inch groups at a 100 yards, no lie!
Only drawback is you have to use the product's arrows, and they are little pricey as well, at $90 apiece.