Back from a London-Edinburgh trip.
Arrived early in the morning at the London Hilton on Park Lane hotel after the trans-Atlantic flight and we were immediately checked-in. A nice start to our stay. The room was an upgrade to one of the Executive Floors (26th Floor). Unfortunately, it was the smallest room on the floor (most of the rest were suites). There was virtually no room to walk around the queen-size bed. It had a shower only, no bathtub. Finishing touches were beautiful, as was the view over Mayfair, including Buckingham Palace, Big Ben, the Eye, etc. Major complaint was noise from staff entrance (swinging doors at the end of the hall immediately outside the door to our room), with staff coming and going at all hours of the night. Requests for a quieter, larger room were met with an offer for a downgraded room on a non-executive floor. We passed on that 'opportunity'.
Possibly due to the number of suites on the Executive Floor, we had security (police/Scotland Yard?) in the next room as neighbours, with at least one and often two on duty in the hall immediately outside the elevator at any given time. No idea who the distinguished company was, but there were four police motorcycles and a Land Rover around much of the time. We were definitely safe!
Executive Lounge was on the first floor, so a short elevator ride each time. Decent breakfast, excellent hors d'oeuvres and scones at tea time, and decent hot and cold hors d'oeuvres in the early evening. Free wine and drinks. You cannot take any food or drink out of the lounge - not even a coffee to go. Attentive service (tables were cleared quickly after people left). Free wireless was available in the lounge, as well as one computer for guest use. It was never too busy to get a table, although sometimes the overflow (room without any windows) needed to be used. The view from the main lounge room was out on to Park Lane and across to the park. All in all the lounge was a nice sanctuary.
The elevators had a curious system where the floor selection needed to be entered while waiting in the hallway - the buttons in the elevator did not respond (do not change your mind after you enter the elevator!).
It had a decent sized gym in the basement (no pool). Parking is prohibitively expensive, and paid separately (not on the hotel bill - no Hhonors points

).
We went to two excellent restaurants in the Shepherd Market, immediately behin the hotel (less than 3 minutes walk).
El Pirata is a relatively inexpensive and absolutely delicious tapas restaurant. Highly recommended.^
Le Boudin Blanc is a cozy French restaurant, although a little expensive (but frugal compared to the top-priced London restaurants). The meal and service were both top-notch, and I have no reservations in recommending it.
Even though the Park Lane may be a little west of central London, it was only a brisk 30 minute walk to Covent Garden, and much less to the shopping streets (Regent, Oxford).