I own both the Waterproof H1 5/10mm and K01 8mm. They're both great hoods; I have a lot of sub 40f (36-39f/2-4c) dives with both of them. I think you'd be happy with either.
I owned the Waterproof H1 hood first but I haven't really used it since switching to the K01. I have a brand new Waterproof hood sitting in my bin as backup hood if that tells you anything. I'm currently on my 2nd K01 hood. I just find them more comfortable than the Waterproof hood. The neoprene is more stretchy and form fitting. The Waterproof one does vent a little better but the K01 has a tiny pinhole in the top that does vent, albeit slowly.
One important thing to note that a lot of people seem to overlook is that you should replace your hood after couple diving seasons especially if you're doing a lot of deeper diving. I typically replace mine after 2 seasons and retire them to warm water hoods until they rip enough and then they get tossed. I see a lot of people on boats with 5 year old hoods.
The difference between my 2 year old K01 hood (lots of 100-200ft+ dives on it) is amazing. The batteries in my digital caliper is dead but you get the idea here. Left is a 2 year old K01 8mm hood (maybe ~250 dives) and the one on the right is brand new with maybe 5 dives on it. Be careful with sharp finger nails and pulling on the seams of the K01 hood. They can tear more easily than other hoods.
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That difference is pretty amazing, thanks for the pictures.