You might want to check out how the amp measured, noting especially the channel separation and clipping power into 8 and 4 ohm.
Moonriver 404 Reference integrated amplifier Measurements | Stereophile.com
Anyon have experience with Moon River Reference 404 Integrated?
Any our Audiogon family here see, feel, operate, hear one of these in the wild or at a dealer? I'm intrigued by this product.