Just out of interest Briney - if you're still reading this thread : Have you checked out any other naval games yet? Granted, those are the first two that come to mind when I think of submarine games (well, replace SH4 with SH3 for me), but there are also a lot of other games out there that might catch your interest.
Also, I really think that DW isn't
that complicated. Admittedly, it takes a bit more of reading and practice (for me: a lot of practice) than other games, but after all, that's why we love simulation games
Doesn't mean I want to talk you into playing it
There are two demos on the Sonalysts homepage, one for the Kilo sub, and one for the Seahawk. These could give you a first impression.