Rikenon contest: game over (almost)
After assembling a decent group of Ricoh lenses I gave them a semi-rigorous testing at 35, 50 and 70ish mm. I am incapable of being truly rigorous, as some variable will always creep in - but I am satisfied that they all had an equal chance to show off. I used Live View with 6x to get focus as good as possible. Both in ease of use and image quality, the winner was the 35-135 f/3.5-4.5 P one-touch, with 28-100 a short step behind and the 28-80 f/3.5-5.6 further back. The 35-135 is 500g so heavier than I'd like in my man-focus walkabout, so I may try a few more before it's over.. but for now it's the best of my bunch, and still 100g lighter than the 28-100! All lenses were sharp enough, but contrast was stronger on the 35-135 so less processing would be needed. All are prone to contrast loss with bright light on the front element.
I did not throw the Promaster 28-80 into the mix for these tests, but if I do acquire a few more lenses I'll try it with the 35-135 and future set; in some ways IQ looks similar to the 35-135, and size and weight are nice. However, it's showing its age with some play in the focus/zoom rings; the 35-135 is very smooth and a pleasure to use. I'd forgotten the fun of a 1-touch since they were outlawed in the late '80s (kidding here, I think).