How does Cycles compare to V-ray. Is there a "dirt map", fur and displacement?

Hello there.

I’m using V-ray for my works, but I would like to know if it’s feasible to use Cycles instead, because it has an “unbiased” approach I think it’s easier to setup and achieve photo-realistic results.

The first question is regarding the speed. I know Cycles make good use of GPUs, and can achieve a good speed for stills provided you have a high-end GPU, but what about fly-troughs? I don’t think it scales as well as V-ray because as far as I know it simply renders all the frames one-by-one, so you can simply num_of_frames*time_per_frame to get the approximate time to render the entire animation, what makes it prohibitive in terms of time for animations because it a frame renders in 2hour, and you need a 5min video at 30fps, you don’t have to even calculate that to know it’s not viable. While V-ray uses the global illumination (LC and IM) data in an intelligent way that saves a lot of calculations, It doesn’t recalculate every frame, it “recycles” the calculated data, so it really scales much better and you also have much more flexibility to fine tune the settings. So, what kind of speed can I expect both for stills and fly-troughs?

Also, I couldn’t find a material/texture that produces “dirt maps”, V-ray has this feature and it’s one of the most useful for me, there’s a way to use vertex colors, but that’s not what I want. And I’m not sure also if you can make fur like V-ray, with thickness so you can use it for grass and other stuff other than fur/hair, and also if there’s a vector displacement map. Is there a way?

Thank you in advance.

Best Regards.