I like both bands and I see the similarities but I get so sick of every Victorian-ish goth band with a female lead singer being compared to Evanescence
I don't mind at all because I 愛 both bands, although I 愛 Nightwish もっと見る によって a long shot. I can see how they're kind of similar, so I understand why they get compared sometimes.
I've only heard one song from Nightwish and I liked it but I've heard quite a few from エヴァネッセンス and I have liked them all but they both still good bands from what I've heard about Nightwish