in light to moderate rain and light winds it's OK and only a little rain comes in, so I rig it above the hatch in the head where it doesn't matter. But in a driving downpour or high winds it's useless, even using low-stretch line.

The hatch tent is just a square of cloth with grommets and takes almost no space to stow. You can get the hatch tent at Defender for about $70 whereas this ATN product is $250+ depending on size. Is it worth it, or is it another one of those gadgets that sort-of works, and takes up more space to stow than justified? With overhead hatches open (and cabin fans) we have never felt the need for wind scoops (but we rarely stay in marinas) but once those hatches are closed all the way it's another story, even with the companionway open.

We also have a passive/solar flush vent in the head but I think that's just about useless. I would put a dorade there but I'd also have to get a stainless guard to keep the headsail lines from ripping it out, and when you consider finish headliners and all -- it's more of a project than justified for the relative benefits.