I am a proud owner of a Griffin LT which is probably the most fun kayak I have owned to date. While it is pricey for a recreational kayak the build quality and performance justify the cost in my opinion. Walrus as a company has been delightful to deal and work with. Mark is without doubt has got to be one of the top PR people that any company could wish for. From shipping to questions, Mark has been outstanding and polite.
As for the Griffin itself, it to is very pleasant and enjoyable to paddle. I weigh 185 lbs. and am 5' 11" so I am on the large end of the scale for the Griffin. Because of this the boat sits a bit lower in the water and is incredibly stable, just like a recreational craft should be. Compared to my Eddylines and Current Designs that I have had in the past, the Walrus is the most responsive and easiest to paddle. My LT weighs in about 5 pounds heavier than advertised but is still easy to car top. The Griffin sits low in the water so wind is not as big an issue as some other boats. The Griffin is a very wet paddle though and a spray skirt is a welcome addition.
One aspect that I appreciate about my Griffin is that it has a very shallow draft and I can get into and over very shallow areas of water. The Griffin has decent speed for it's short waterline and seems to glide well. I use an Epic Mid wing paddle with the Griffin and that seems to make for a very nice efficient fit. The deck on the LT is angled nicely and there are no problems with hitting any part of the deck no matter what type of stroke you have. My boat has no skeg nor rudder and sometimes I do miss not having a rudder but the Griffin responds well to input.
As for the good I would have to say: fairly light weight, very good looking, comfortable layout, and just plain fun to paddle. Don't forget the wonderful customer service.
The not so good: mine is a little heavy for being carbon. You won't win any races with the short waterline. Mine seems to scratch very easily even though I am very careful and baby it. You do get wet if there is a wind. Storage on the LT is limited, but this boat is not a tourer anyway. Quality is good but not in the league of lets say an Eddyline. The seam line tape is not very attractive.
All in all, if you are looking for a fun responsive kayak that just seems to do everything pretty well and you don't mind spending to get it I think just about everyone would paddle a Griffin LT and have a smile doing so