I bought the EOS M on a lark - it was cheap, a guy traded me one for a 28-135mm IS. I toss it in my bag and used it only for fun. Then I broke my arm, and the EOS M was the only camera I used for months, after which I grew quite attached to it.
Even with the firmware upgrade, yes I admit that focus is acceptable but still on the slow side for street, which is where I use it the most. It gets lost from time to time, and focus is pretty useless in semi dark conditions.
Then I tried the EOS M2, and I thought WOW, this is amazing. I fell in love for only the focus speed because of how quick it is over the M. The price tag, however, was not so amazing. M3, on paper, sounds even better.
I don't plan to go solely mirrorless - my criteria was primarily cheap fun for street, and I won't cry if I break or lose it. But every upgrade path from the M seems to get into serious money very quickly.
Any of you switch from EOS M to M2 with no regrets? Is there another camera/system that I'm missing?