The show is entertaining but as usual, I have to agree that it would be so much better if they did more accurate tests. As everyone else mentioned, there's the whole Ninja thing (They never fight head on, and should have been left out entirely), bringing siege weapons to a 1 on 1 fight (In the Aftermath, the reason was "because it was cool"...Seriously!?), having completely different tests, and a lot of times they don't test each weapon against each armour.
One of the most weirdest ones was grenade testing in Green Beret vs Spetsnaz. The tests were completely different and I have no idea how a proper conclusion can come from it. One grenade is in a laundry machine with targets outside in an area. The other grenade test is in an enclosed space with targets inside the room...
Generally I dislike the gun episodes but like the ancient warrior ones.