I was out club racing in light winds recently, having a go in a Phantom, with Dzeros, Lasers and Solos out too. Going downwind, they were all able to crouch with one buttock on the side deck to get the right amount of windward heal, whereas I was having to full kneel on the double bottom cockpit floor, inboard of the sidedeck, being a much wider boat. My knees were in bits the following week. The Dzero looked particularly comfy in this mode, with the nicely rounded inboard sidedeck edge, the Solo has a thwart which also helps, but the centreboard case capping messes it up a bit. The Laser has a narrow cockpit which helps too, you can be proper sitting while only slightly to windward. The Hadron feels strange in this mode, with the wide centreline tank, like being in bed with a really fat chick, sure you could get used to it. The Finn wins the downwind ergonomics hands down. The Blaze and 300 are the opposite, you are kneeling all the way, fine in your 20's, tricky after this. Haven't sailed an Aero yet or OK yet. For me, it seems that the depth of the cockpit is not as important as the positioning of the side deck, for boats that sail deep downwind.