It has the best conclusion in all of flash comics. It tastes as good as a mcdonalds chicken wrap with bbq and ranch inside, it is a pretty awesome comic and its worth reading at least once.
This part has all the spoilers
wally west wakes up in barry allen's body in another reality, iris is not single(don't worry they don't dwell on that), the world is at war, thomas wayne is alive and cyborg is this worlds superman, oh and superman's a coward, and the antimonitor is about to be erased from history.
The best part of the comic is the subtle use of facial expressions to show emotions as if you were watching a movie(the movie is also a great watch). It also has a powerful message of letting stuff go, without the annoying singing of frozen, and if you want to read it, you'll need to read it slowly to enjoy it. You can also find this free on viewcomic.com(all 5 volumes).