Well, I've owned M2 (chrome), M3 (chrome and BP), M4-P (black chrome -- eurgh!), MP (BP), and used M6, M7, M6ttl. For me, the MP is the nicest of all (especially with the Leicavit), followed by the M2. I don't like M3s (wonderfully smooth but no 35mm frame, no meter, strange rounded frame corners) and I sold my last one years ago. Between the M2 and the MP, viewfinder flare has been a problem for me
Does this mean I'm wrong and M3, M4 and M4/6/7 owners are right? No. Does it mean they're wrong and I'm right? No.
Everyone has their own priorities. Choose yours. No-one can really do any more than tell you what worked for them, often on the basis of not having tried very many Leicas, and sometimes on the basis of never having used some of them very much.