Yeah... as I said maybe SH10
I just tried out that open source subsim, and despite is being a little dodgy and rough around the edges... the ocean graphics are bloody amazing!
It has to be seen to be believed!, the wake of the sub, the way the ocean ripples, the recflection of the sun on the water... bloody amazing, it looks real, far better that in SH3, and not even what I've seen of SHIV looks as good. The only thing missing is the actual wake rippling away from the vessels, but the foam looks real