Spent a week at the St Pancras Renaissance and it was wonderful! I am Platinum and would have been upgraded to a nicer regular room, but they offered a Chambers suite for 125 pounds more a night, and while a splurge, it was money well spent. Just look at the photos. I have never been to a hotel where a lovely rubber ducky is provided for your luxury bathtub. We rarely paid for a meal as the Chambers Lounge provided complimentary hearty buffet breakfast and afternoon tea as well as midday and evening offerings. The most fantastic thing about this hotel besides the service, is the literal abiilty to step from the 1800s to the 21st century just by crossing a threshold. You travel from the historic train station to the modern one in one step - you are immediately on the concourse and the Eurostar service is steps away. Down a level is a wonderful mall of stores -- Fortnum & Mason, Marks & Spencer, etc. Everything you could need, and Marks is open until 11:45 nightly. The service at the hotel was exemplary with every need met. HUGE full size bathroom amenities.
One thing though -- if you are a light sleeper or not used to the big city sounds, you will probably need the several provided earplugs. A major hospital is just up the street so there are sirens a good deal, however even the sirens seem to be polite -- there was a noticeable point in the evening after which they were not used unless needed. Noise abatement perhaps? I woke up every day thinking "Manhattan? No, wait, London." I love white noise and sound at night, so it was ideal for this sleeper. This hotel is in the middle of all the action. You are short tube or taxi rides to Covent Garden and anywhere you'd like to go. Walk to the British Library across the street and see the Magna Carta. Walk to Kings Cross and have your picture taken at Platform 9 3/4 photo op that includes a luggage trolley going into the wall! Buses stop right in front of the hotel. I would stay here again in a second, we were very sad to leave! Make this a splurge, get your Platinum upgrade, whatever you have to do! The hotel is visually stunning and has starred in both Harry Potter and Downton Abbey filming!