Which Class D Amp to Buy?

I am thinking of upgrading my Flying Mole DAD-M100 mono amps to something better (I love them but can't help thinking there must be something better than these over-achieving $400 amps), and am trying to decide between the new Flying Mole DAD-M310 monos and the Spectron Musician III SE (about double the price of a pair of DAD-M310s). I need to avoid tubes since the amp will also double as the front channel amp for my HT system and tubes would burn out too quickly in that application. Anyone listened to both? My system consists of a Zero One Mercury server, Supratek Chenin preamp, and Zu Druid/mini-method speakers. Any help is appreciated.