I have been going through my Crunchyroll Queue, re-watching, and watching the shows I just added. It is to see if I want to keep them in my queue and to understand why I saved them in the 1st place. Dimension W was one of the shows I didn't remember watching, even though it said I watched it. When in it, I remembered parts but not everything, so I watched all 12 episodes to see why I kept it.
After re-watching it, I can see why I kept it. I always root for the underdog and love at least a decent ending. That is what we got from Dimension W. We get two protagonists who we learn to understand and go through their trials together. Then we get an ending that shows you can hold on to what is true and move forward through a painful past.
I'm not too fond of the way it tries to push for romance for the two protagonists. Being partners and friends is a better look than romance. I am also not too fond of the "higher-ups"/governments ending or set-up; I think that could be better. However, story-wise and the set-up of the world would only lead to that ending, so I understood. I also think the climax of returning to the island could have been better. They kept harping on how this colossal incident happened, it was being kept under wraps, and it was the worst thing ever. I would have liked it if the emphasis matched the reveal. However, the reveal was anti-climactic and not all that bad. If they were going to do that, reveal I would have rather it be one of the many incidents that happened and the government is covering up.
All in all, it is worth it to re-watch Dimension W. I would re-watch it again if there is nothing else to watch.