The back hatch cover never seemed very good to me except for day trips with an empty boat. It is very watertight but the soft cover takes some time to put on if you want it to stay on. Also hard or sharp things bouncing around in the hatch might cut the fabric, so I heated up a Hurricane oval cover with a hair dryer and greased it with 303 and made it fit my Epic. It is hard, water tight, and quick on and off. I still feel like it needs a strap or top to really keep it in place for times when I get washing machined at the inlet.
The V7 has no day hatch and no good place for your keys and your snacks, so I popped in a small hatch from Hurricane Kayaks. It is very handy and if I want I could but my tent and a bunch of other long skinny things up here for a camping trip.
These hatches have made the boat a lot easier to use and it is still air/water tight.
I'm thinking about adding some deck lines like sea kayaks have but they would cause trouble with low hanging branches on river days. So for the lake I'm looking for a better leash that does not tangle. So far I like my old paddle leash best, but you must not let go of the paddle.