I also have the mkII subs, which I love more, I think that the MK III are less powerfull then the MKII, the MKIII have punchy bass, but not so deep they throw sound much further then the MKII, a big improvement is the weight and the accesories, more rigging points and a really good improvement is the front grill. So they are for large events clubs or concerts outdoor where high spl is needed.