I loved the premise and it was very well executed. Different and varied characters came to life by great acting, with actors like Charles Dance (Tywin Lannister in Game of thrones) and Toby Stephens (Captain Flint in Black Sails). As the situation gets more dire, you see the true self of these people and I loved how the show focused on the mental state of everyone and how they were coping with this.
The cinematography was gorgeous. The show was really well shot.
Now, my main issue with the show was its three episodes length. It was just too short to fully develop a large character set and while the show did a good enough job with the time it had, it often felt too rushed and even predictable at times. If there were more episodes, many of the characters would have been explored more and more tension would have been created. Also, wasn't a fan of the ending.
All in all, it is a great mini-series, marred by a stupid production choice.