It always depends on the raiding group I would say. Not all bosses suit your raiding group while other bosse are fairly easy. In this encounter I just have the feeling that the tuning is a bit strange. Mabye it's ok for 25, but in ten man it feels kind of clunky. First 6 minutes are boring and then it hurts like hell. I would prefer a little bit more damage in the beginning and a little bit less in the end. Otherwise they could just skip the first 6 minutes.