However, I'm not convinced that mainstream users will get comfortable with it (because it looks "different"). This, plus the fact that enough problems can exist from creation/sharing/clicking that it's likely just not worth the hassle.
Maybe it's just me, but lack of compatibility is a high price to pay for a character (or two) shorter URLs.
It only beats our own ri.ms shrinker by three characters, but that's still something people might consider. And because it uses unicode, it will be a very long time before it moves beyond even 2 character suffixes.