Reviews are filtered through the prism of our preferences and experiences. In my case, I was not thrilled by river runners trending toward shorter (slower) lengths, soft chines and bulbous volumes. A few years ago, one manufacturer bucked the trend and I jumped on it. It was okay, but the hull was semi-planing and the edges weren't aggressive enough to suit me. Then, the Zen cometh.
It's long by today's standards, so it's got the speed for attainments. You can almost shave with the edges, so it'll carve turns. The volume is in the right places and doesn't inflate the hull where you don't need it.
The footboard is easy to adjust when you're on the fly. The backband employs the Jackson design, which is to say, simple, lightweight and easy to repair in the field. Inside is a carry loop to take some strain off the shoulder. Nice touch. The knee pockets are somewhat low, giving it a snug, old school feel of control. And, it's a full-on planing hull for great surfing. Jackson has also gone with duel bottle holders and has improved the grab handles..
The result is a kayak that responds when you go to the whip for attainments or need a burst of speed to hit the right line. It tracks okay (little too much rocker for my purposes, but I understand that in a boat this long) but put it up on the hard edge to get the bite you need for a tight carve. It's stable, predictable and rolls well. And, it loves to surf.
In short, it's a pure river runner that hasn't been dumbed down with soft edges and bulbous ends. If that's what you want, give this one a try.