My wife and I owned this kayak for one season. It proved to be a quality boat with good performance but had one major flaw that resulted in us selling it and getting a different model.
We found that the Muktuk was fairly stable and reasonably fast. It wasn't as stable as a kayak designed specifically for beginners but it wasn't bad and we took many rookie paddlers out in it with only one ever managing to flip it (on glassy smooth water). Speed was decent. It tracked straight, turned with moderate effort (easily with the rudder), and handled heavy seas well. The fit, finish, craftsmanship, and quality were excellent for a plastic boat.
The major flaw, and the reason we sold the boat, was that it could be uncomfortable on your knees when they were nestled up inside the hull, bowed off to each side in good paddling posture. Not everyone who used the boat found this to be the case, but about half of them found that their knees hurt by the end of a paddling session. This was my wife's boat and it hurt her knees so it had to go. We now have a different model and her knees no longer get sore, and no friends have ever complained of sore knees either. In its defense, the Muktuk was designed for small paddlers, so maybe only very small people can comfortably paddle it (but it didn't seem like a particularly small boat or kayak).
I was able to do self-rescues fairly easily and the boat lent itself to leaned turns.
I am still looking for the "perfect" boat and am trying many fiberglass boats that cost several times what this one does, but it is still in the running.