Hi, I bought one of these last week. I'm completely new to network streaming. Up to now I just used CDs and occasionally played mp3s via PC line-out. I'd been wanting to get a bit more out of the many mp3s that I had on the PC, and I also wanted to be able to play FLAC 24/96 like you do.
I've been really impressed with the Denon on the whole. It's very easy to setup and I reckon the quality is excellent. I have been ripping my CDs to FLAC and to me the quality of these files streamed via the Denon is just as good as the CD playback via my Marantz CD6002 player. Downloaded FLAC 24/96 files sound great - as you'd hope they would! Lower quality mp3s (e.g. 128 and 192) also sound better than I've heard them previously.
The only reservation that I have about the Denon is the user interface when accessing files stored on the PC. You can either access directly via the Denon's 'media server' mode, or use Airplay. Airplay is fine if you only have Apple files, but you can't airplay FLAC for instance. And, based on reading I've been doing on the net, I suspect that airplay is not capable of streaming above CD quality. I'm currently waiting to hear back from Denon on this question.
If you don't use Airplay, then the Denon media server interface is a bit fiddly, although this can be improved by organising your files carefully. The Denon remote app for iPhone is a bit slow.
Overall I'm very pleased with it though, and I think it's excellent value at current price.