not only does it turn in quicker it also has a greater contact patch than even a 180/55, they make the bike feel like a 600 in a way, its def worth the extra money if you ask me, i had one on my gixx1k190/55 has a rounder profile, supposed to turn in a bit quicker than the flatter 190/50.
General consensus suggests 190/55 is the preferable size given a choice.