I just ate at Rai Rai Ken about an hour ago, and I feel pleasantly full.
The place is teeny-weeny, and seats maybe 12 people on stools at the counter. There is only one (small) table, and if you sit there, you'll be surrounded by hungry people waiting to be seated; better to sit at the counter. My wife, daughter and I have been to Rai Rai Ken before, but only at odd times, due to its tiny size. Our last visit there was during a blizzard, and today we went on a Sunday afternoon, while everyone else in NYC was watching a Jets game.
My daughter (13 years old) got the basic Shoyu Ramen for $8.50 and it was hugel she couldn't finish it. I got the Mapo Tofu Ramen, with pork and tofu; it was spicy and wonderful. I was able to finish it completely, and also helped my daughter with hers. Mama had the miso ramen, which is vegetarian.
We got an order of gyoza dumplings that were fine, as well as a $2 plate of pickled daikon radish. I drank a buckwheat ale, which I expected to be like a stout, but was more citrusy, like a wheat beer. A good time was had by all.