Gasket Material for Hatches, Lockers, etc.

[off-the-grid]

The gasket on my sail locker has a few pretty big gaps on it, also getting some water in my port aft locker (pretty sure from rain), and for god knows what reason it appears the manufacturer of my boat decided the engine compartment doesn't need a gasket. Considering all the fresh water I found in there after a storm a while back, and the fact that I just repainted the bottom of my engine, I disagree.

After searching around a little it looks like closed cell foam (Taco Hatch Tape, Hatch Cover Tape) is more common than rubber at most of the marine stores. Although it's a lot cheaper than rubber, I'm concerned with how good of seal it will make and how well it will hold up compared to rubber gasket.

Someone on another board recommended this stuff.
W.J. Dennis® EPDM P Profile Rubber (521/ACE) - Rope Caulk Weatherstrip - Ace Hardware
But considering how thin it is, and the fact that it's ribbed, once again, I'm a little concerned about how well it will seal. Also, the rubber gasket I have found at the marine stores isn't much thicker than this stuff.

On the other hand, considering how much pressure I need to put on my hatches in order to lock them, maybe the gaskets I have now are too big...or at least bigger than needed.

Help! Looking for any suggestions on what type of gasket to get. I'd really like to buy this stuff and install it just once...and ideally not have to replace them again for a few years.