Originally posted by wmmk is 28 or 35 going to be closer to the perspective the eye sees when mounted on a K100D? that's really what I'm going for.
Try it with your zoom. Fixate the zoom ring with some tape and see what you think. I have no problems using the FA35/2.0 as a normal lens. Others prefer a slightly wider FOV and choose the FA28/2.8.
To me the difference between f/2 and f/2.8 is a big step. The FA35 is fully useable wide open and very good from f/2.8 and onwards.
In theory the FA28 should be closer to some loosely held definition of what a "normal" lens is (measuring the diagonal of the sensor) but as said that is a matter of personal taste.