I got the M3 to test it out, as it intrigued me. Also my M2's SDC burned out. Other than that, my M2 worked great for 2 years, and the power regulation part still does.
First impressions of the M3 are mixed. It is tiny... It does what it is supposed to. Amp turn on works perfectly.
Some bad things, are that the jumpers are not standard 0.1" jumpers. They are teeny tiny and standard jumpers dont fit. They are loose when you put them on.
Also they took away the 30second/2hour setting for the SDC, which renders the SDC useless for me as everything is way too short a time for pulling the plug, or way too long for pushing the power button. So pretty much completely useless timer options.
I will need to get the serial connection, or just buy another M2.
Anyone want an M3?