The site itself contains many "player quotes" which (naturally) wax lyrical about it's qualities. The system has been around for some time now and is clearly successful although I've not yet owned a guitar that sports it.
Another alternative and more recent system is FRETWAVE which seems to be a novel way of tackling the same problem.
I never felt this was a problem when I was younger, or more likely, just couldn't hear it, but in recent years I find myself tuning and re-tuning quite frequently and I may consider a retro-fit on one or two of my own guitars.