Interesting comparison, the conclusion for me being that the differences aren't really worth losing sleep over...unless losing sleep is a sporting thing for you. 😉
One of the things that I've always strived for when putting together a multi-lens camera system is a degree of of optical continuity. I've never much been into the idea of needing that 50mm lens for its unique wide-open bokeh rendering (not that bokeh is totally unimportant to me), or this 28mm lens because it possesses an MTF chart that's the dog's private parts. I want all my lenses to be good, of course, but I want them to be on the same page in terms of color rendition and contrast, and that mostly happens when the lenses in question are from the same "litter" for lack of a better term. (It also helps a little in terms of lens handling and "feel" when switching from one optic to another, but that's a bit trickier.)
When I decided the Hexar RF was going to be my Main Axe, I also decided that I would have just three lenses, all of them M-Hex: 28, 50 and 90. The 28 was my first lens, which I got together with my first HRF body, and it truly knocked me out in terms of quality...possibly the best 28 I've ever had, and I would say I've had a few damned good ones. The 50 came next, and didn't disappoint...nothing "stands out" to me about the 50, or, for that matter, the 28 or 90. They simply do what I expect a high-caliber lens to do, under all sorts of lighting conditions, and without surprises.
Microcontrast is good, but gestalt, for me, is gooder.
- Barrett