A very nice hotel near Shinjuku Station, making this a great base for staying and getting around Tokyo.
The hotel is modern and well maintained, but like most hotels in Japan and Asia, space is never wasted, a standard double room is typically 15.8 square metres (171 square feet), enough for one person to stay comfortably, but a squeeze when there is two in a room. If your travelling with someone consider paying more to get a deluxe room, but holidays are not meant to be spent in a hotel.
Standards were high and service excellent, if you book directly with the hotel you may find a special offer if staying more than two nights, which includes breakfast buffet that has a mix of Japanese and western food.
Though the Hotel Sunroute Plaza Shinjuku claims complimentary high-speed internet access, this is only through a wired connection, and no wifi available throughout the hotel (as of 2012), though this is something I found common when searching for hotels in Japan.
In terms of price and value, Hotel Sunroute Plaza Shinjuku delivered above expectations. Its location is enough worth staying here, and the standards are high, with nice in-room touches such slippers and even a sleeping gown/robe.
Hotel Sunroute Plaza Shinjuku was a great choice for exploring Tokyo. Thumbs up!