I tired a few faux finishes in the past and did not have much luck. I was able to do the finish, but you know how you work small areas at a time? well, when I stood back and looked at the whole wall, you could see where my small areas were, because the technique was slightly different from area to area. In general, I just couldn't get a uniformed look.
Now of course this is all just experience, but I had very little, and it showed.