Celestine is a top 4* hotel (don't expect 5* facilities). I was positively impressed as I ended up there- sceptical - during the busy IMF week and our usual corporate hotels were full.
Good location, Nice lobby, friendly staff, nice well equipped room with decent size for Tokyo standards. The bed was comfy, the view through the big windows very nice. I had north east facing and could see the Tokyo tower.
There is free wifi across.

Highlight: there is special filter coffee package available something I haven't see elsewhere.

Only downside? There are not linked with any frequent flyer programm.

I did not try breakfast.

My husband and I stayed at Celestine Hotel for 4 nights while we were in Tokyo. The hotel is a short walk from Toei Shibakoen Station, as well as Mita Station (exit A10 / A8) which has both Mita Line and Asakusa Line. Hotel staff spoke reasonable English, and were all very helpful. Their breakfast buffet was excellent both in terms of quality and choices!!!

To save some transportation costs, my husband and I bought the 1-way Airport Limousine tickets with Tokyo Metro 1-day Passes (promotional price, about 400-600 yen off the full price). The Airport Limousine dropped us off very conveniently in front of the hotel. (The Airport Limousine tickets alone is 3,000 yen per person, but if you throw in the Tokyo Metro Pass, and but them as a set, it only cost you 3,100 yen per person. There might be a minimum purchase of 2 sets, though.)

I stayed here for five nights while attending a conference at a nearby university. The staff were very helpful and spoke reasonable English. My room was a superior double on the 17th floor, I had a view of the building opposite with a bit of Tokyo between it and the next building. But even that was amazing from the 17th floor. My room was plenty big enough, with table and chairs, TV, huge comfy bed, big bath, and a fair bit of space to unpack into. Reception provided me with an adapter so that I could plug my laptop etc in, and I had free wifi. Breakfast wasn't incredibly good, but it was incredible, for the weird mix of food on offer including salad and pasta dishes. I'm told the Japanese breakfasts were great, I was happy enough with my eggs and toast, and cereal. The bar in the hotel is quiet but really enjoyable, and the Japanese gentleman I met there told me that the bartender is famous. There is a book of cocktails in the bar, and the barman is in the photo on the back. He makes good margaritas, and there is a large whiskey selection which my friends made headway with. As a solo traveler, I had an enjoyable meal in the restaurant on my first night, that's the last time I had western meals as Japanese food turned out to be amazing. The hotel is really well located, because its only a short walk from four different train lines, and in around Mita there are some great little restaurants, including an outstanding Ramen bar which I would direct you to if only it had an English name. I've try to put a photo of it up, and a map, so you could probably find it if you want an adventure. I had the special dipping Ramen, it was just amazing. The next afternoon we went back for Gyoza, and they were the best dumplings I ever hope to have.

I stayed at the Celestine Hotel in Tokyo for seven days on a business trip. The hotel is located within the central Tokyo area, and easy access from Narita airport via the Airport Express train to Shinagawa Station and a short taxi ride from there. The hotel is located on the 14th-17th floors of a corporate building, with a spacious lobby, café and restaurant on the ground floor. My room, a twin room, was a corner room on the 14th floor with fine views across to the east, and views of Tokyo harbor as well. The room was really spacious, and the daily care of the room was careful and attentive. It was a lovely room, and one that facilitated work with a spacious desk and good internet service. There is a very nice lounge with an outside smoking and non-smoking zone on the 14th floor as well, providing a relaxed area for coffee, tea, water and biscuits which are available throughout the day and evening. It provides wireless internet as well. The Tavern & Grill Grand Cross, located on the ground floor provided an ample selection for breakfast – with a good selection of western, Japanese and vegetarian options. I thought it was fresh, tasty and enough variety over the seven days of stay. The hotel staff were the essence of courtesy, helpfulness and willing to answer any questions with patience and thoughtfulness. The hotel is just a short walk to both Mita and Shibakoen stations on the Mita line. If you are planning to do considerable travelling around, certainly buy a Suica card (at the airport or at any station). This will allow you to move through the multitude of privately owned train lines with ease, and it will let you know when you need to top it up! Otherwise it is a complex and time consuming process of buying endless tickets, and this can be a hassle when you change lines. For the health conscious, the hotel does not have any fitness facilities at all.