This thread ecouraged me to get my MP out for some shootin' And unfortunately I was using the wonderful Zeiss Biogon-C 21mm...
If this had been an M7, I could have set to AE, zone focused and used the external viewfinder and shot away, but I find using the external VF on a full manual camera a pain. So, as to your question on MP vs M7, there it is, the M7 is easier in those situations. Heck, the Bessa R4A would have been the ideal experience!
But, I'm still keeping the MP. As I don't use the 21mm all that much.