I used my 210 f/4 for the first time for the shot I entered in the Ilford/APUG contest, and I was really happy with the result.
I particularly like the fact that it takes the same filters as most of the rest of my Mamiya 645 lenses, and will also fit the Mamiya focus assist lever that I really like to use with my cameras.
Matt
Good point about the filters.
2F/2F
"Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."
If the 210/4 would fit my needs, I would get it in a heartbeat. I have learned from experience, however, that I need f/2.8 for a lot of my work. Between shallower DOF and higher shutter speeds in low light (ever shoot cycling photography at dusk with a medium format camera?), the f/2.8 is what I need.
Well, can it be worse than the 210? It is supposed to be better glass with APO correction and the 2.8 opening. Other than the price it should be a much better lens and as you said the only thing that will do the job for you.