I traded my A4 for a MnM because I wanted the extra assignable outputs and two extra tracks, along with more versatile machines. I didn’t really regret it at all, though I did miss the nice A4 reverb and the mini keyboard for pitch inputs.
There are some sounds the A4 can make that the MnM can’t, but a LOT more sounds the MnM can make that the A4 can’t. I already had other analog synths so I went for it.