I am 6'9" 250lbs with a 38" inseam and size 15 shoes -- no SINK for me. Bought the Zone 2nd hand in May for 1/2 retail price as a replacement for my OK Prowler 15. It is in mint condition. I was looking for a higher performance SOT for ocean kayaking and longer distance trips.
Due to some short-term health issues I have been unable to spend too much time on the water this season. However, I have gotten out enough to share the following observations thus far: This is a well built boat. Very good fit and finish. Hatches are very well constructed--rear tank well is open with a net--well engineered, but a hatch might have been better. Initially, I found the boat to be very tippy compared to the OK Prowler with its soft chined hull. However, after a few minutes and some lose hips that feeling dissipates. This is a very fast boat--almost surf-ski like. It is designed for fast long distance touring. It does not turn exceptionally well, but for its length and hull design it performs as intended.
I replaced the existing rudder control system with the Smart Track Toe Pilots. After some major re-engineering (a long story) they were installed and greatly improved my ability to handle the boat. My center of gravity was lowered with the addition of 1-2" of leg extension and now having the benefit of a firm brace point for the feet is key.
If you are tall and/or are looking for a higher performance SOT this could be the boat for you. Other than a handful of the more "exotic"/ boutique SOTs from S. Africa, this is probably one of your best choices.