I know that they occupy quite a lot of floor space is it sticks out quite a ways to the right-hand side of one's table saw, requiring adequate open area to the right of your saw to accommodate such, though I do not doubt for a moment that it does precisely what Incra promises. I generally love Incra accessories but while I did look at this solution once upon a time, about 10-12 years ago if I recall, I could not see what this really offered above and beyond a quality Bessemeyer T-square type fence. It is certainly a tremendous upgrade over a crap fence, but next to a good quality fence it is no more, or less, easy, in my opinion, to get comparable accuracy from a traditional fence that does not occupy nearly as large a footprint in my shop (where floor space is always at a premium). For example, with my Bessemeyer type fence, if I want 11-23/32" I simply slide my cursor to 11-23/32" and I know for a fact that is the distance between my fence and blade without needing to double check the measurement.
Keep in mind that while repeatability and accuracy are important in woodworking that they are also relative since wood is a natural product that changes in dimension from one day to the next with changes in season and humidity. If you can reliably get better than about 1/64th inch accuracy and repeatability out of your woodworking tools then you are in good shape to build most anything you wish without much concern for anything more accurate than that (thicknessing, inlay, and specialty joints are about the only applications that typically require better accuracy). You need enough repeatability and accuracy to ensure you can reliably remake a damaged or flubbed piece, but no more than that as a few swipes of sandpaper, or a small change in humidity, will frequently dwarf any precision much greater than that.