Yeah, I think it's a good choice. That is essentially a dacmagic plus (which I have been using extensively for a while and love) with a wireless streamer. It doesn't do airplay but that's not an issue for you since you rely on flac files.
Mac Mini (as server) -> Squeezebox Touch, AE express->Cambridge Dacmagic Plus -> Outlaw RR2150 Stereo Receiver->PSB Image T^6 (dedicated 2 channel system)
Mac Mini -> NAD T747 -> PSB Imagine B, Samsung UN46EH6000, Panasonic dmp-bdt220 (home theater family room)
Macbook-> audio gd fun "b" dac/headphone amp -> audioengine N-22 amplifier -> audioengine P-4 speakers/Energy ESW-M8 sub/Beyerdynamic DT 880 (home office)