Tried PEF mode and something interesting happened. The non-DR shot was 14,599 kb. The shot with DR on was 12,549 kb. Upon importing into Lightroom 1.4, they were converted into DNGs which measured - non-DR 12,932 kb and DR-on 11,438 kb
They shrunk. Out of curiosity, here are the snap shots. They are a bit small as jpgs to really note the increase in noise, but you can see it on the facing side of the speaker, even small (ISO 800). One can note the trace contrast boost for better or worse in the speakers face (along with the yellowish hue). The reduced flash signature on the can may possibly also attributed to the wider range of highs in DR mode, or perhaps the angle being slightly askew of the original shot, hard to say. The shots were only resized as jpgs, lens used was 31 ltd.
OFF- ON-
EDIT - I would be curious to learn why the in-camera DNGs are literally double the size of PEFs converted to DNGs, both were exported in adobeRGB. Anyone?