Sonic Syndicate was forgettable. Completely and utterly mediocre, at best. The best parts of the songs were keyboard leads...but there's no keyboardist in the band. It would also help if the band didn't sound like Killswitch Engage or, as Nick said, "These guys sound like Atreyu." Well now I've confirmed why I don't listen to Atreyu either. At the end of their set they announced it was their last song and there were a few shouts to the effect of "Thank god!"
Nightwish, however, was amazing. Normally, when you go to a show, you tend to enjoy the songs you already know well. That wasn't even the case here. The songs I knew were good, but some that I didn't know ranked among my favorites of the night. Let me get one thing out of the way now, Annette is not Tarja. Her range and operatics just do not match Tarja's at all. But if she is taken on her own and not compared to Tarja (though she performs songs Tarja originally did), she is actually not bad really. She's a more subdued voice, and has less focus in this new version of Nightwish, but it's by no means ruined by a lack of Tarja.
In fact, all five band members were, in my opinion, essential performers of the night. The keyboardist is a great player and also quite entertaining. The bassist (the other vocalist) not only provided a good stage presence, but had good, fun stage banter too. He even was well-versed enough in Colorado lore to know that Colfax (where the venue is located) is known as a street to pick up whores, and make a joke about it. The drummer has as much stage presence as most any drummer can have, about 1 in 2 songs he ended up on top of his set jumping and giving the crowd energy. The guitarist was also great fun to watch and had some great solos (especially the improvised harmonization with the keyboardist, that was awesome). Annette did a great job of not only singing but continually engaging the crowd, dancing, doing whatever she could to keep everyone entertained, and it was effective.
Also, unlike far too many bands, Nightwish does not play live like they do on CD. The songs are different, there are added sections, there are neat recordings added not from the album, and it's great. I pay far too much money listening to bands play what I already own, only with worse sound quality. Not true for this band.
Also, the band did a great job of making the show feel intimate, and they are so friendly they were still greeting fans when I left 5 minutes after they stopped playing. They were so appreciative too. Rare in bands that are well-known in their music scene.