Apart from the shorter sight radius of a 16 inch barrel, please list all the DISadvantages.
16" barrels are awesome and one is in my future... but one other disadvantage is weight for balancing a PRS rig.
Ideally, in this setup your balance point should be a couple inches in front of the magwell and weight further out from this balance point allows you to have an overal lighter rifle than one with a shorter barrel.
That is not to say people are not shooting PRS with a shorter barrel and happy, but most folks are running a longer, heavier barrel, even though they are competing at 300y distances with a .22. The velocity loss and manouverability are generally seen as lower priority than positional stability.