I had a 20 or so hour layover in Tokyo, and Ueno Terminal Hotel was in a good location to get to Akihabara, Asakusa, and Ueno. The staff at the front desk spoke English and check-in took barely a minute. The room may be small by American standards and I am a giant but I still had no trouble fitting in the room or the bed. Still, if you are thinking of sharing one of their smaller room, don't (unless you don't mind someone sleeping right on top of you). The toilets are far more advanced than anything I've seen in America. The shower/sink combo took a little figuring out but should be no trouble to anyone with basic problem solving skills. The wifi was plenty reliable enough. I did not visit the in-house restaurant/bar (as a general rule I do not), so I can't say anything about that. Likewise, I cannot comment on room service (which is offered) because I do not use room service if the hotel is within walking distance of a good convenience store (and Ueno Terminal Hotel right in the middle of plenty of them).
The only issue I had was trying to find it without Google maps. This is not really their fault. They are on Google maps but I was coming out of China and my phone is still having trouble reconnecting to Google. Still, I found it in under half a hour, so if you have a traveler SIM or a Wifi anywhere app, you should be able to find it right away.