I have paddled a kevlar-carbon Tahsis for 4 months now and have found it to be the best kayak I have paddled to date. I am 195#, intermediate skills, and normally paddle a Shenai.
The Tahsis seems to have replaced the Arluk1.9 in Necky's line up, but with a Looksha multi-chine hull and a inverse keel. It is both fast and quick, and I won a race recently in it. A nice balance between tracking and turning. It has a light initial stability and moderate secondary. I removed the whoppie cushion and soft pad seat cover to increase the comfort level and lower my center of gravity. This made an impressive increase in stability and removed a problem of my legs falling asleep. The air cushion is now used as a camping pillow. It's really a dumb idea for a performance kayak seat.
The cockpit is the best I have ever sat in now. Leg grips are super firm, low rear deck, and a seat back that allows you to rock back to lay flat on the rear deck - snug fit with cyclist thighs. Smart track rudder paddles are great. The rudder blade seems to drag during rolls (when it is at rest position). I only once used the rudder during the race, think I might take it off in the future. I would give it a ten but I have not paddled all the other kayaks yet.