I'm considering installing a couple of hatch vents in my Freedom 30. Current thinking is a Lewmar passive vent in the forward hatch over the v berth and a Nicro solar vent in the hatch in the main cabin. My reasons for this combination are: the Lewmar vent doesn't hang down beyond the inside surface of the hatch, it's said to be 100% watertight when the bung is in place (a good thing, esp. on the foredeck), and there's little point in a solar vent here when the hatch is often shaded by the furled self-tending jib. I'm assuming that the Lewmar vent can be installed in a non-Lewmar hatch.

I'm not sure how effective a solar vent will be in the dark, rainy PNW winter, but if anywhere, the main hatch would seem to be a good place for one.

I'd be grateful for opinions from those with more experience of these things than I have.