Been listening to an M-4 through the R-117's MC phono front end. Was on the Sony SS-M7s but switched to JansZen CFIIs. Pretty efficient for E-stat hybrids and it's a smaller room, but I will have to try one M-4 per side just because.
One of these days we will all be sorry when the M-4 is universally recognized as the sleeper amp it is and the cost goes up. Built like a brick, easily rebuild-able, parts are easy to come by, adjustable, powerful, and are clean and enjoyable to listen to.
