If sealed it's not so likely to stain, but all marble will etch. It's up to you whether or not that's going to be a problem. If you go to the kitchen forum there are several threads about etching, with photos so that you can get some idea of what it looks like. Etching will be more obvious on a polished surface than a honed one.

What writersblock says. We have marble in our bathroom and it is etched all over - even water can etch it. I don't mind the etching, but i'm sure it would bug some people. You can go to a stoneyard and get a sample and etch it yourself and see if the look will bother you. In terms of staining, I'm pretty impressed with how the sealers make it almost impossible to stain. My dd has hot pink toothpaste that she smeared on the white woodwork (big timeout) and I couldn't get the stain off the woodwork no matter what I tried. But she always gets it on our marble counter and even if I don't clean it up right away, it doesn't stain.

I have it in my master bathroom. The counter near the sinks has some minor staining, I haven't noticed any etching (it's honed). The floor near the toilet, on the other hand, is a mess. Less of a "missing" issue than a "splashing" issue, I believe.