I ran a few quickies of the scene-in-progress, each with the area light with IBL, just IBL, and just sun. The IBL alone is still fastest as expected at 113ks, but the area light with IBL wasn't a slouch either at 86ks. The sun by itself was about the same, but you just can't beat the sharply defined shadows (for a large scene anyway) it produces. Simple 'portrait' type scene is a bit different, but not my specialty 

It was still interesting to try it out nonetheless! 

crimsonworx.com; free ebooks and previews

I've bowed down to facebook: https://www.facebook.com/crimsonworx