Fast enough for what it gives . . . . these scenes here no more than 10 minutes each. Not sure how long FrankT's efforts took but they're bigger renders. I was limited by the 600X450 restriction on the demo version.

I like the way light behaves in Vray with easy setups.

in the very top pic: 5 lights-four omnis in the light meshes and a shadowless fill omni near the camera

Middle pics: a sun from the outside and an omni in the hall near the camera for fill

Bottom: a sun from the outside and a shadowless omni near the camera for fill

Below: a sun from the outside and a shadowless omni near the camera for fill

There are other apps that light that quick and easy though. I think the depth of focus in combination with the lighting is what sets Vray apart from what I see.