I actually saw this new musical when I was in London recently and it was excellent, a great night out.
If you like We Will Rock You, then you will love this. Rather than being set in the future like WWRY, this one is set in the past in the mid to late '80's and has the excellent soundtrack of the time. Check out the classic rock songs, Here I Go Again, The Final Countdown, Don't Stop Believin, Wanted Dead Or Alive, I Want To Know What Love Is, We Built This City and many more from the period. If you grew up on this stuff and you were there at the time (like me) it's a great trip down memory lane.
The singing is brilliant as is the dancing and overall performances from all the cast.
If your in London and you want to see a musical then get your ass down to the Shaftesbury Theatre and rock out.