Almost good, but sadly buggy.
Silent Hunter IV truly is a beautiful (looking) game. The detail that has been put into ships, people, weather, explosions and the sea will awe you. When I first started playing, much of my time was spent without any time acceleration just so I could admire the interior of the submarine itself and how it is modeled.
Additional features have been added to the game to streamline the day to day operations of the ship. One in particular that I like is the use of watches to allow for your men to rest on their own without the tireless juggling found in stock SHIII to keep them from collapsing from exhaustion.
Regardless of these good points, nothing good can come out of the bugs and questionable setup for some of the game design. Without belaboring the issue I will simply recommend to future buyers that you wait for another patch (1.3 has been “sighted” at least – see this link http://www.subsim.com/radioroom/showthread.php?t=115309 ) and take a view at subsim.org to see what they are doing to fix it.
Until this tuna can receives some further support though, it is being mothballed.