Thomas Morgan , Feb 20, 2006; 05:49 p.m.
I put a sample of the 70-210 F4 for you to look at here. The camera was a 7D, hand held, with the image stabilizer running.(*)
I can't compare the two lens, but maybe this sample will be useful to you. In terms of durability, the 70-210 is built (and weighs) like a tank; it could double as a field expedient weapon, should need arise :-)
In general, I have been pretty happy using the older Minolta lenses purchase used. I like the look they give images. The main drawback to this one can be slow or cranky auto focus.
(*)If you are wondering where I got the model, I happened to be down under the Manhattan Bridge and came across a commercial shoot. It offered a nice test of the lens and the image stabilizer