I've been paddling for a couple of years now and own a Necky Looksha Sport, a very different beast from the Nantucket altogether! My wife wanted a wider, more stable boat, and found the Nantucket's cockpit very comfortable. I've paddled it a few times, mostly on the local river ( the Huron in SE Michigan) and its impoundments. At cruising speeds, I find the boat very easy to paddle and handle, and it's very stable for birdwatching and photography, and, presumably fishing and hunting as well.
However, it is not a fast boat by any means. It is much harder to paddle fast than my Looksha, but then again, it's quite a bit wider and heavier. I've also had it out on Lake Erie once. In some windy chop, it was quite stable and tracked very nicely. Since it is short boat (14'9"), I did try using the rudder to offset wind induced weathercocking. The rudder really does the trick, but is not really necessary except for the worst kind of weathercocking.
Overall, I really like this boat. It's not particularly fast, but it has great initial stability, good secondary stability, and handles fairly well. The Old Town foam sandwich construction makes for a handsome and extremely stiff boat, but also adds considerably to the claimed weight (it also makes for a warmer cockpit in cold water as it insulates quite nicely). Hatches seem quite dry, and the overall fit and finish of the hardware is good -- much better than I've seen on some of Old Town's older models.
This is a very versatile boat for beginners: stable at all times, usable on large flat waters (great lakes and oceans) as well as broad rivers and impoundments (I don't think I'd use this boat on any fast moving water unless I had a lot of room to maneuver as it's not the nimblest boat), plenty of dry storage for kayak expeditions (especially if fresh water is available), and at less than 15 feet, pretty easy to store and transport (although the weight makes rooftop loading a bit difficult).
An agressive paddler would probably outgrow this boat pretty quickly, but it's a very nice boat for anyone else, and offers great value. We picked up the expedition package for $875 -- quite a bargain compared to other small expediation ready sea kayaks!