The hotel is excellent situated across from T4 and with a private walkway from the terminal, there is no need to cross any airport roads. The atrium of the hotel, where reception and lobby bar and restaurant are located, is more than you'd expect from an airport hotel. Reception was most kind and efficient. Our room was on the third floor, on the T4 side. Looking at but not hearing the airplanes so that will not interfere with your rest. Dimensions of the standard room are on the smaller side, especially if you are traveling with a companion and you both have suitcases.The room itself, though, looked a bit tired. It was clean but it had definite signs of wear and a bit tatty here and there. No other rooms were available, unfortunately. All standard amenities are present. The wifi signal in the room was non detectable and from what I have understood, quite expensive at GBP15 or so per 24hrs. In these times of smart phones and tablets (not to mention notebooks and laptops) I honestly feel wifi should be offered standard at no charge in any hotel. It appears that the bigger the hotel(chain), the more expensive wifi is. If the golden arches and coffeemakers can in all of their branches, I think a hotel can, too. I understand the necessity to make money but I also feel the hospitality industry should be able to find a better way than using wifi as a milking cow and maybe reinvent itself.
In this particular case, the Hilton T4 airport hotel does offer FREE wifi in the lobby with ample signal. And although the login process was easy, I couldn't get it too work. However, this was resolved quickly and most friendly by the lady at reception. This hotel offers excellent and friendly service and good on site amenities for everybody who chooses to stay at the airport. I can recommend this hotel.