X10 vs X20 Studio Comparison

I'd say, forget about the background. It reflects light differently in both shots (it's a reflective "blinky" type of cloth) and the angle is different, too.

Where exactly do you see more information on the main flower? I only see higher contrast, more sharpening and more sharpening artifacts and more information drowned in darkness in the middle. If you take a look at my comparison crops you will notice that there is ​less​ information/detail in the grass in the X20 image (likely due to NR).

By the way, I just noticed an interesting fact about that "30%" claim: "Dark noise suppression"!

Other than contrast and processing differences this would also explain why shadows in the X20 images are so dark in the shadows. Noise may have been cut-off on RAW level, aka filtered out to(wards) black. We had a discussion about the E-M5 possibly doing that, but didn't come to a clear conclusion. Its black levels do behave slightly different at different ISO, though.