Originally posted by Jonathan Mac I've had a couple of copies of the A and found them to be sharper wide open that the M, but other than that no difference. The A setting is useful but the gritty, broken plastic feel of moving the aperture ring on the A make it unpleasant to use on a film camera, so I've sold both copies I've owned. I have three of the Ms - one for home, one in my parents'-in-law's house and one at my own folks' house - that way I know I will always have a good 50mm available wherever I am.
I've heard the stories about most of the A lenses having junk aperture rings. I don't understand why Pentax did that; I know it's cost savings, but how much was really saved at the volume they were producing those lenses, and what impact did that have on their reputation as a lens manufacturer?
I could definitely see having a film camera, an M 50 1.7, and maybe a 24 or 28 of some sort to form an extremely basic kit that sits in a desk drawer or closet, waiting for you when you need it and didn't bring something with.