The first time I heard the CD I couldn't get past the fact that it was catchy and not heavy enough. But the more I listen to it, the more it appeals to me. Frankly, I can't STOP listening to it. Fans of the heavier Within Temptation style will no doubt be disappointed and grumble "Sell out." There are no growl vocals - no MALE vocals at ALL on the entire album. But, of course, Sharon's vocals are gorgeous and I quickly got over the lack of meatier male vocals. Some songs are clearly lighter, poppier if you like, but a number of them have the heavier beat and atmospheric sound you'd want from WI metal songs. In particular, the song "Iron" is a winner.
Overall, if you want the darker, metal of earlier WI, you will be disappointed. But this is something different. Lighter, catchier, hummable, it totally sticks in your head. Remember it's a concept thing and not necessarily indicative of what WI will do in the future. Enjoy it for what it is.