I read this last of the three semi-linked Matsumoto stories (Space Battleship Yamato, Captain Harlock, Queen Emeraldas). Just like the other two, this one has a very loose story t it which ultimately does not wrap up or really go anywhere. This may be even more true than with the other two, where we just get one small story that we follow along with.
I found this the least appealing of the three. I was hoping it would wrap up some questions we get in Captain Harlock, but it doesn't really. We do get to see a cameo or two in it, but nothing that really answers what that book brings up. This book has the smallest cast of characters and usually that is what made the others pretty fun, interesting personalities around the ships getting into hijinks and adding some comedy. This keeps a more "dark and mysterious" tone about it but given its not even a complete story - that works less to my liking.
The art I also found less impressive, the other two books had some really great panels that were highly detailed and impressive. This one had a few that were okay, but nothing that made me stop and go "wow!"
So anyway, it's okay. Less worth it than the other two and as such hard to give a firm recommendation.