I have to say, the Mac 4100 is such great receiver - and I have owned dozens of receivers.. My biggest like? All those I/Os. Here is the list: Phono 1 Phone 2 FM AM Aux 1 Aux 2 Tape 1 I/O Tape 2 I/O (Rear jacks) Tape 2 I/O (Front Jacks) Headphone 1 Headphone 2 Speakers Set 1 Speaker Set 2 Speaker Set 3 The manual says nothing about running set 1,2,3 in any order - the 100W/75W power amp can drive a 2 Ohm load, so it does not matter how many you run. Add on to that a Mono button, FM Muting, 5 band EQ, adjustable Loudness and full featured AM/FM Tuner. Plus, LED power meters. OK, the vinyl casework is weak, but I have a custom mahogany case on mine and it looks great. And, some do not like the "non-McIntosh" look, but it is OK and usable. I have two of these, and I really can not see ever "upgrading" them.