I found Nihombashi to be a convenient location once I figured out how to get to/from the subway station, especially the one and only subway station enrance friendly to roller bags.
But it's not quite so easy to figure out. Exiting the station, I had to wander all around (inside the combination of two stations) until I found the one roller-friendly exit, and then I tried to take notes about how I got from that exit to the hotel (and that first time, at night, I didn't get there as directly as I could have, either, the first time). But I still had trouble finding the same exit going in the reverse direction!
Of note, I had no GPS. Probably if I'd had a portable GPS on me then it would have been much easier (once I'd found the exit out of the station, I could tag that, then once I found the hotel, I could tag that, and then I could go back and forth between the two really easily.
I can't comment on the other hotel since at the time I was doing the stay the Nihombashi was the only one availabile on points. So I used it two times (at the beginnging and end of my stay -- in the middle of the stay I moved to outside of Tokyo).
I really like the breakfast buffet at the Nihombashi, there was a large variety of Japanese food to eplore, but also enough Western food that I could fall back on in case I hadn't liked any of the Japanese food.
I wouldn't mind staying there again at all on a return trip to (or through) Tokyo. (But like I said I'd bring some sort of handheld GPS this time!)