My neighbour and I bought a couple of these for mucking about on the canal. We've ended up taking them all over the place, down rivers, out into the surf... and we're already planning a week-long mission for next summer. (You wouldn't believe how much stuff you can cram into these things.) I love mine so much that I commute in it! You really can't beat this for fun-for-the-money.
One thing to watch: The seat is attached by a thin strip of material, and for us this began to split after just a couple of weeks' use. The tear heads straight for the main buoyancy chamber... I'd strongly recommend cutting the seat off as soon as you get the kayak. Inflate the seat and put it flat in the kayak with the longest dimension running side to side, and it'll stay in place quite happily. You could supplement that with Velcro if you wanted. To be perfectly honest, you don't really need the seat at all.
Chop the seat off, show this the respect that any inflatable needs, and you'll love it.