Mak Hobby compares the paintball rifle, Tiberius T4.1 to Airsoft Gas Blowback Rifles in this video... "Putting the Tiberius T4.1 beside a few nice airsoft replicas of M4, M16, PDW and such to let you see the difference and similarities betwen them. Overall, I would say that the Tiberius T4.1 is really outstanding and is very close to an AR rifle overall, plus maybe the straight mag of the FAL and such!

Airsoft GBBR mostly uses Green Gas, which is injected to the magazine, but because they are lower pressured gas, they do not provide enough power to bang out a big projectile like the paintballs and such in 0.68 Caliber.

One very huge difference and advantage of using HPA is that it is not affected by temperature most of the time, and so the power is very consistent and will not be dropping or having any cool-down issues."