It was okay. I live in the city but sometimes grab a hotel if I want to change up the venue, or if I have someone to meet. I had to do both, and decided to give it a shot, since Fairmont and Accor are one now, and Pullman is part of the family.
Part of the problem trying to sum up the experience is that I have no idea what the Pullman brand is supposed to represent, and no experience staying at Pullman-branded properties.
The location is convenient, if you have to take the Yamanote around, but entering the hotel is still a bit awkward (this might have been fixed, now that the construction should be mostly complete). The basic room was a deluxe version of a typical room in a Japanese business hotel, only slightly larger, with the same amenities. Strangely, there was nowhere in the room to work, except on the one area of counter space that's beside a giant sink basin, which is fine, I guess, but it limits the space available and if you go over to wash your hands or whatever, you're splashing soapy water on your Macbook. I know it's not set up for business meetings, but it's inconvenient for even a brief face-to-face. But that's whatever.
Otherwise, the other spaces in the hotel are comfortable, but not incredibly exciting. Pleasant staff, absolutely by-the-book check-in and check-out.
I'll choose it again to rack up some points and give it another chance, but first impression is that it's kind of whatever. I fear that like every other hotel in Greater Tokyo, they will hear the siren song of package tours from China, and the price point is low enough that it doesn't keep out Australian backpackers loitering in the lobby with giant backpacks. But what can you do?