I installed the Lewmar Open Ocean hatch without flange on Mithril last summer and it has been great. Easy job. I used 4200 and also had to fill in old holes and redrill.
Was this for the V-berth hatch or the small head/salon hatch? Either way which size did you use. My hatches are done and I want to replace them this winter. Just need to get a handle on which hatches to order
After looking at the different Lewmars this weekend I would like to try the low or medium profiles versions but I'm not sure if they'll fit without modifying the deck. A little more research is required I guess.