I own one, I bought it second hand 10 years ago. I like it as a modern alternative to an M2 with more reliable viewfinder/rangefinder being so much newer and not made using balsam. I don't doubt there are many M2s out there with perfectly fine viewfinders and rangefinders, just my personal preference.
It has always worked as advertised, I prefer not having a meter, personal choice - my other cameras don't either. It is the same as an MP without the battery for all intents and purposes. There are subtle differences in the framelines and it is a different colour but I don't think those things merit specifically needing an M-A.
I imagine there is less online chatter about the M-A as there are just less of them and they just work without issue, there's not that much to discuss. I love mine but I prefer my IIIc FWIW! I'd enjoy your MP and not worry about the M-A. I have no idea what the hyphen and the 'Typ 127' signify, it's just an MP minus the electronics but with a hyphen and a subtitle!