To my knowledge, VRay is not part of 3ds max but costs additional $299 to $799. I have never used Vray (I don't own 3ds max), but I'd be very surprised if it were able to deliver displacements at speeds similar to a REYES renderer while still retaining it's raytracing speed. I can only gather information from web sites, and there I read things like " Displacement really is a hog on the system so it will require a healthy dose of.. patience." - which is something you'd never hear about a REYES renderer. Also, it looks like VRay requires you to determine the micromesh resolution before rendering (at least it looks to me like that in the screenshot) where a REYES renderer is dicing the mesh based on how many pixels it occupies, so the resolution automatically matches the object size on the screen. And again, my point was not that displacement is impossible in 3ds max or C4D - but in such renderers, the overhead over non-displaced rendering is significantly higher than in REYES renderes like PRMan (just try with Poser 5 - the speed difference beetween a scene with and without displacements is close to none). P5 can render animations as a series of still images, no problem. And IIRC, both TIFF and PNG files are being saved with an alpha channel.