There was a line outside the door during the last day of the Japanese spring festival (sunday) about a half hour before it opened. Luckily, the restaurant is surprisingly large and we were able to be seated in the first round. The waitresses took orders very quickly and because it was a busy weekend, there were only a set menu of ramen and their special soy sauce chicken dish (15 orders).
We ordered two tonkatsu DX ramen after reading through yelp that they were the most flavorful over the chicken ramen. However, when we saw other tables receive their soy sauce chicken dish on a hot plate over bean sprouts, our mouths were watering. Regret not trying that dish out!
When you order, you have an option to adjust the spiciness. We both got mild and it was sufficiently seasoned. The noodles were just great, definitely different from the typical noodles I'm used to coming from out of town. The broth wasn't too salty and was very tasty probably due to the fats :)
Service was quick and easy, since this ramen place might be busy for awhile, the waitress would come by mid meal to give the check so right when you're done eating you can head out! You can be in and out in 30-45 minutes so if you wanted to wait for the second round of seating, the wait won't be terrible. Highly recommend trying this out if you wanted to add to a list of ramen places to eat in SF.