Raffay, Yes, they are the ones and It's all about glass. I own all 3 and use them with my Pentax MX and my DSLR (I know it's a curse around here). They manual focus just fine, but when it comes to glass, this are some of the best lenses Pentax made.
I especially like they way they render bokeh, the 31mm is outstanding here, very smooth, considering it's wideangle and many wide angles are pretty bad at it.
I also do own few other lenses, like 24mm f2.8 (I'm selling it) etc... I just use this 3 all the time. With the 31mm and 43mm spending most of the time on my camera, but it depends on the focal lengths you like to use.
Best thing is, on MX and ME Super when I use 43mm I can have both eyes open and perspective/magnification is exactly the same. It's perfect 1 to 1 as if the camera isn't there.
Last edited by Nuff; 11-08-2013 at 08:29 AM. Click to view previous post history.