This is what I play these days instead of HarpoonTM - it's much simpler and more playable but it does have a few rough edges.
The rules include several novel and ingenious ideas to reduce complexity without sacrificing realism. And in a wargame of modern naval combat reducing complexity is vital.
The semi-abstract submarine rules are particularly clever. ASW operations are very difficult to simulate on the tabletop without getting into time-consuming and complicated mechanisms like plotting or dummy markers. The Shipwreck system is the best I have seen and produces very tense games but after several sessions it was clear that there were a couple of problems.
It seemed a shame to let such a great idea go to waste so I modified some of the rules and adjusted some of the numbers and the new rules are now being tested.
As we did with HarpoonTM we always play double-blind with limited intelligence on a map. We use either pencil and paper or a PC with Aide De Camp 2, and transfer to the tabletop when contact is made. Both map and PC methods were developed by a friend of mine in our local club.
The rules are relatively new and there is good support on the web both from the publishers, Vandering, and players.