A fully split Advantage is a really interesting prospect. I have a Freestyle Edge RGB at home that I really like, and an Advantage at work that I haven't used in over a year.

My biggest complaint about the Advantage is the placement of the arrow keys in the bottom row. I never got used to them (and I sometimes use vi with a Dvorak layout). I hit them by accident far more often than on purpose. From the survey, it appears to me that they are still in approximately the same location.