Beyond the stated advantages of back inflate BCs like the KH, the Classic can be a bit difficult to get in and out of, if it fits properly (that is snugly, or else your tank will move around), because it doesn't have the shoulder release buckles. No shoulder release buckles is cleaner--and with the Classic offers the apparent advantages of wrap-around air (but you'll need to really fill the Classic at the surface to keep your head out of the water in rougher seas, because the air moves up into your shoulders). I used a Classic for years and it's a great BC--rugged as can be. But it really cleans things up in the front having the air in the back. Moreover, a tightened up KH will keep your tank rock solid on your back, and you can don and doff it with ease (just pop the buckle). My 2 cents only.