I did not receieve my order yet, so I cannot review it.
My S50+ powers a pair Polk Audio Signature Elite ES15. At low volume there is a noticeable hiss. Not a deal breaker but annoying. The Phoenix style connector limits speaker wire choice. It could really use bass management but for $200 it does a decent job. I will be put this in my garage and upgrade to the Bluesound POWERNODE Edge when it becomes available. I would have scored it higher but the audible hiss is too annoying.