DELICIOUS.
GO.
NOW.
There is sometimes (usually) a long line up outside. The first time I went was last year freezing temperature. Waited half an hour outside with my toes freezing off. COMPLETELY worth the wait. And I'm sure everyone else in that line thought the same - why else would they wait so long?
I would definitely recommend the tonkotsu or tonkotsu black if you like more flavour. Ask for original noodles.