The mAMP is based on the ICEpower Class D module. If you want the "latest" Class D, maybe look into the ncore amps. A couple of examples for 2-channel
ATI AT522NC - $1695 from soundapproach.com
Nord Acoustics "One Up" model with discrete Class A input op amp. About $2k USD shipped.
Nord also has a larger variety of amp choices based on the ncore module.