Quote Originally Posted by BobD View Post
The ME was marketed as an "entry level" SLR. Its features were much like the Nikon EM -- auto exposure only, no manual mode. Price was low end. There were some other similar models such as the MV, MG, etc.

The MX was marketed as a manual-mode SLR for pros and had pro-oriented accessories such as a bulk film back, better meter, optional focusing screens, etc. The "X" in its designation was meant to position it with the LX, Pentax's flagship pro 35mm SLR at that time.
I wouldn't even bother with the ME. The ME Super is a mush better camera. And the Super Program better still (though a bit bigger and the VF a fraction smaller.

You get the MX because it's better than the K1000 and is mechanical. But if you want the meter and the battery then the options above are better IMNSHO.