Wait is a bitch there. We usually get there around 5:20 to guarantee a spot when they open. They're not as efficient as Fukada and don't seat the entire restaurant right when it opens. Here's a tip:
If you miss the opening bell and the list is way long, make sure you check bar seating. The guy doing the list seats the bar last and around 6pm he will call out to people who checked bar. And you will jump ahead of everyone else and get the stink eye from the crowd as you swagger into the restaurant. If you don't mind the bar and for us it actually works out better with our little one sandwiched in the middle so we can take turns helping her eat. But make sure it is the front bar, near the sushi chefs and not the rear bar seating near the yakitori chef, those are counter height and kills my lower back.
And skip the tatami room, stinky feet is a nasty buzz kill. Hello fungus! (and yes they NEVER clean the restaurant, don't look around too much, you'll lose ur appetite)