I play paintball (woodsball and scenario) competitively, and I have to say that it does not assist me in anyway in INS. Furthermore, it's funny when military guys come to play paintball with us because they always think that they will dominate because of their training. What they don't realize is that the maximum effective range is 150ft on most paintball markers (unless you have a flatline barrel, or are playing with non-regulation fps.) All my army friends said that they qualified at 300m with their m16, and my marine buddy said he qualified at 400m+. Furthermore, paintball markers are just that, markers, not guns. They fire a spherical, soft projectile which means that it is prone to curving more than a cone-shaped bullet. Also, because it is soft, you cannot have a rifled barrel (yes, I know they sell them, but it's a scam) because the paintball will break before it even leaves the barrel. Plus, the lower speeds of muzzle velocity on markers are much lower than that of a bullet fired from a gun, so wind will affect the trajectory of a paintball much more dramatically.