Can’t comment of the Marantz unit but I do have the 803 in my living room system paired with Meadowlark Herron I’s and I think its a fantastic bargain. The sound quality is very good for the money. I’ve had more than a few costlier amps in this system and the 803 has more than held it’s own. To name just a few: Kinki EX-M1, Primare I30, Hegel H160, Yamaha AS2100, Wells Audio Majestic, Denon PMA 160one, Vincent SV 226 mk, SimAudio i3.3. For the money you can’t go wrong with the 803.