We had the 12 piece band from Rembrandt and they were phenomenal and we received continual accolades throughout the reception for the band (sometimes you could swear it was the original artist). We had the keyboardist only during the ceremony, a jazz trio during cocktails and all twelve pieces for the reception (and they played continuously - rotating so that we wouldn't have to have an ipod during dinner - then only a soloist and keyboard). They kept the party lively and even donned sunglasses and fun hats (Elton John, Ray Charles) to keep the party vibe going. They have an extensive song list and were generally very accommodating (they will only learn one new song) with keeping the music lively throughout the evening. In fact, two people want to hire them for their upcoming events.

Amazing band! Soooo much fun. We couldn't get people to stop dancing!

I got married 2 years ago, and people are STILL talking about how great Rembrandt was at my wedding! They definitely set the tone, and could sing/perform ANY style of music. They've played at my sister's wedding and at a friend's wedding, and were great there as well.
They are pricey, but its worth it.