My Danby Marble Tests...
I must say this stuff in impressive. I had a sample of polished Imperial. First I dropped some balsamic vinegar on it and let it sit a bit. Rinsed it off and no etch. Then I let it sit overnight, and when I rinsed it there was very light etch. I could hardly see it even when the light was roight. No change in the surface feel, and it was much lighter than an etch would be on the Italian marble. Going to try both tonight to see the difference.
I also dropped some red Kool-Aid type drink mix on it. The powder form mixed with a touch of water to make a dense again paste. You all know how this stuff stains. I wiped it off after a minute or two, and with some slight scrubbing it came off. I then left it to sit for a few hours. Washing it off left a pink stain. Scrubbing lightly with a paste of Comet and water wouldn't take off the stain. I made a paste of some Comet and water again, but let it sit overnight, and I just rinsed it and the stain was completely gone. No trace of pink! I didn't notice any etching from the Comet either. They tell you to use this on the honed finished to clean and to remove etching. The totally honed finish looks so flat though.
Now I should state that all this was with NO SEALER on it. It should perform much better with sealer. So far, I'm really impressed. This is good stuff.
Next I'm going to try an edge chip test, and scratch test.