Well, I may not agree with you...
First of all, I know it might be strange, I hate Nightwish!!! ...but love Within Temptation and Evanescence.
I don't agree with you when you say that Nightwish and WT are better than Evanescence... (just my opinion)
I just think that Evanescence were very much punished, because they came out after these two bands... And everyone started to say they copied Nightwish and Within Temptation, when actually these three bands were formed almost at the same time...
I hate Tarja's voice, she has probably the most hugly female voice I've ever heard in my entire life... Don't give me wrong though, I'm not saying she can't sing, but I just hate her voice...
Evanescence seems to offer much more than those two bands, and they certainly are much more successful... The last Nightwish and Within Temptation albuns were both a huge deception, and we almost see that they can't go much far because their best was already reached... Well we saw the worst side of Evanescence, their commercial side, but they are going to release a new non-commercial true metal goth album... Seems they are here to stay...
I can't deny I love them, but from my point of view, they're at the same point of Nightwish and WT now, and they can even be better than them...