My friend directly compared the Technics SU-R1000 to the Boulder 866. He sold the Boulder 866.
I've listened to the Rotel Michi Integrated amplifier and their mono-amps. In my opinion they're both mediocre.
Gryphon sounds very good, but after a really good friend's recent experience with repair of his Diablo 300 integrated amplifier, I would never purchase Gryphon.