I went to Oedo Onsen Monogatari in July last year and enjoyed it -- mostly. The only bad thing was dealing with the Yurikamome, which is slow as molasses, and in the summer has pitifully bad air conditioning.
They had bus service from near the Yaesu gate of Tokyo station, and Kachidoki, so those might be good alternatives (or take the Rinkai line to get closer and then hop on the Yurikamome)
Actually my last 3 nights in Tokyo are at a hotel opposite the Yaesu gate of Tokyo Station so catching that free shuttle bus would be
very convenient.