Ichi Ni San in Ginza (located in the basement of the Ginza Inz shopping arcade, near Hankyu) is the most amazing gem and unexpected pleasure. They specialise in pork from Kagoshima, Kyushu. At lunch, it's no more expensive than any ordinary teishoku store in Tokyo, but the quality of the food needs to be tasted to be believed. At night it turns into something more like an Izakaya, which I imagine must be amazing. Can't wait to try it in the evening too~
Try it for yourself and let me know if this isn't the best tasting pork teishoku in town!