I've been twice-- once in 2009, and once in 2010. I thought it was a nice place, didn't realize it was actually part of Denner... it seemed pretty fancy to me. But what do I know?
First time was for some after-work drinks and tapas with some coworkers when I was working on a project team nearby. Second time was with a buddy who treated me to a lovely glass of champagne after we saw a Cirque du Soleil show on a Saturday evening. Both times I felt the atmosphere and quality of the drinks/food were quite good.
Anyway, my two cents. Hope this helps!