Rendertime 1 hour, setup time to get it to look a bit like the photo, around 3 hours
Thank you for investing so much time on this.
The mental ray result is quite interesting, especially the fact that you accomplish all this from the hybrid-ND method (the inner engine workings are definately different)
The image looks very sharp (good contrast). Also, it is good we can actually see the bottom ridges through the base of the glass.
The caustic is not well developed; I can see it forming, but is being overwhelmed by the shadows of the straws which are a bit too strong.
You are right about the ambient lighting... it is somewhat off.
The image overall is good though and non of these points would be evident without a reference photo
(we could be arguing for years about what looks right or not without the reference photo)
Again, thank you much for taking time to make this comparizon !