Doesn't matter which renderer you use as long as you know which settings are best for the sort of motion you are producing. But other than that, vray, mental ray, brazil, default renderer - it doesn't matter which one you use.

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[Link to www.3dprevis.com]

true, I guess when you introduce GI into the equation it can cause problems for animation, such as flickering and much longer render times.
I think vray is favoured in architectural work mainly because you can do lots of tricky stuff to manipulate the different Gi methods for static scenes with a moving camera (flythroughs) such as caching irradiance maps and light cache. Brazil and maxwell are both pretty damn slow, although i havent used any of the latest versions of brazil.
Stick with scanline if you have a lot of animation to do, I say...

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