I bought the LL coupe last fall and finally got to take it out recently. This is my first SOT kayak, I usually paddle a canoe and needed something smaller and lighter that I could paddle anywhere and the Coupe fits the bill. My only gripe is that it IS a soggy ride. Water has a tendency to come in through the scupper holes in rough water. I simply got some hard foam balls and plugged up the front holes...problem solved.
It has decent primary stability and great secondary stability as it takes waves and rapids with ease and I never feel it will tip. This thing is all over the place without the skeg though, although I can see how it would help in whitewater. I use this thing for fishing and it is much easier to get around in than my canoe. The Coupe is a great all around kayak that can do just about anything you want to do on the water and it won't break the bank.
I bought the Liquid Logic Coupe because I wanted a cross-over kayak I could use in flat water, light rapids, and the ocean surf. As a comparison, I also have an Ocean Kayak Frenzy. They both perform quite well for all three categories listed above. The Frenzy is actually a bit better for beginners in ocean surf because the hull design allows for the kayak to stay on course easier than the coupe when surfing down waves. The Coupe has the advantage once you get some skills under your belt. The Coupe will out-perform the Frenzy in whitewater situations and will carry more. I enjoy both kayaks.
One issue with the Coupe in ocean waves is that mine takes on a lot of water. I always need to lift it up and drain out the water from the plug after I use it. The Frenzy didn't take on nearly as much water. I think water is getting in the boat from the hatches. The next time I take it to the ocean, I might use some plastic wrap and rubber bands to supplement the hatch covers.
I like the integrated wheel on the Coupe. It comes in handy when I need to move the kayak over hard ground. Over sand, though, I drag it from the back. It's a good cross-over boat.