On the island series kayaks, the bow pushes down underwater in some conditions. A tight seal on that hatch is required. Hatch liners add a possible compromise to the seal, so in their current design... we don't comfortable doing that. If we can overcome the seal issue, we may re-consider.
Matt, I know this is not the thread for this but I thought you should see this rubber seal I have been using to fix the issue.
It is automotive boot or as you guys call it "trunk" seal.
There are two lips one at the top angled out and a lip at the base designed to seal against the car body but here it is protruding enough that it acts as a splash diverter to deflect water back down away from the upper seal.
I am sooooo gonna copy this.