Radisson Blu Hotel South Kensington (formerly Radisson Blu Edwardian Hotel in London)

I have a friend who travels to London regularly and she always told me that was her favorite hotel. However, I have no recent info.

I stayed there 4-6 years ago and liked it a lot.

I stayed there about 28 or 30 years ago, under yet a different but similar name (without the Radisson), and it was fine. Room, as always in London, a little small, but fine.

We took the England tour this summer, and the Radisson Blu was our least favorite hotel of all the ones in which we stayed. This is based on personal preference, obviously, but we tend to find the "business class" hotels less appealing than the smaller hotels that we often encounter on our tours. They tend to emphasize the public areas - bar, lobby, restaurant, - but with very small, very plain rooms. We have noticed a trend in our RSE tours lately for the first and last hotels on a bus tour to be business class, although on the Best of England tour, only the last hotel fit this description.

Yes, the Radisson Blu was "fine." Pros: the public areas were beautiful, spacious, and well maintained. The staff was friendly and ubiquitous. The breakfast was great.

Cons: our room was indeed tiny, our smallest room on the tour. This wouldn't have been notable, except for the price, which I will get to in a minute. Oddly, the Nespresso type coffee maker had only 2 pods of coffee available, one of which was decaf. This in a double room. And other tour members I checked with said theirs was the same. I did ask at the desk for at least one more pod of regular, and was assured it would come. No, it didn't.

We also didn't care much for the neighborhood, but again, YMMV. It was busy, bustling, and noisy, although our room was quiet, even with the window open.

The negatives are minor; I don't usually care much about the size of the room, as long as it's clean. But when I had emailed the hotel before our trip, asking about staying extra nights, the price I was quoted was about $400 per night, without breakfast. If we asked for the breakfast when we booked the room, we would be charged "only" an extra $45 a night.

The hotel we did choose to stay in in London after our tour was about $200 per night for a spacious, comfy room with a hot breakfast included. This one (the Celtic) was on a quiet street just minutes from shopping, pubs, restaurants, and public transportation. Much more our style.

If I were you, I'd check the price of the rooms. We were there in June; it's possible the rates are more reasonable at other times.

There wasn't really anything wrong with the Radisson Blu; just neither our style or our price range.

2019 BOEngland tour. I actually liked to finish with a business class hotel after all the "charming quirks" of the other hotels :-D Convenient to Tube. Great breakfast buffet (I was sorry to fly out early the last morning and miss it! But they had to-go breakfast snacks available for early departures! I also used their car service for early departure, fair price.) The hotel is made up of connected town homes, so there can be circuitous routes and varying levels to navigate to your room. Half-glass shower enclosures that don't keep all the water in (pet peeve of mine and seems like more and more hotels are putting these in :-( Fantastic tour, enjoy!!
Just noticed you're planning to stay a "few" extra days: it's totally fine amenity and location wise if you're staying just an extra day, but for longer, may be worth researching other areas and hotel chains (especially if you have loyalty!)

We stayed there on our 2017 BOE tour. IMO: Yes, the room was a bit small (we have had a lot smaller on RS tours) but the room was clean, the bed was very comfortable, it was quiet even though we faced the street and the breakfast was one of the best of our tour. No, it wasn’t a small B&B but it wasn’t a massive blocks of rooms “Hilton type” either and still a bit RS quirky when trying to find your room. If I remember correctly we were maybe half a block to the tube station and when David did our neighborhood walk we were close to museums and a variety of pubs and different types of restaurants. I thoroughly enjoyed it after having come from York and the hotel we stayed in there which checked all my negative boxes. But we all have different opinions…I like busy and bustling when in a big city like London. There’s plenty of neighborhoods and a variety of hotels to meet almost everyone’s preferred choice.

THIS from SQ was also my experience:
"The hotel is made up of connected town homes, so there can be circuitous routes and varying levels to navigate to your room."

It was a maze of narrow hallways to get to the one tiny elevator on our floor. And a longer distance, with more circuitous routes, to get to a stairway--useful in the event of a fire.
I do agree with Jane in her comment above. Our room was small, and as Jane said "We also didn't care much for the neighborhood.... It was busy, bustling, and noisy,"

Yes, it is in a neighborhood convenient to the tube and to museums...but there are dozens of other hotels in that area, just as convenient to the tube and museums.

One excellent hotel you could switch to is The Rembrandt--right across the street from the V&A Museum. Walking distance to Harrods and shopping and two tube stations.
Let us know if you'd like more hotel suggestions in the same neighborhood.

This hotel was OK for the time the RS tour had booked us in there...however, we moved as soon as the tour was over.
You could also consider moving to another neighborhood (such as Bloomsbury, the area near the British Museum) for a change in scenery.
Most areas in London have good tube and bus service; South Kensington doesn't have a lock on that.

About this, again quoting from Jane:
"But when I had emailed the hotel before our trip, asking about staying extra nights, the price I was quoted was about $400 per night, without breakfast. If we asked for the breakfast when we booked the room, we would be charged "only" an extra $45 a night."

You can do MUCH better than this! You can find something nice for about half the price.
There are several really nice Premier Inns in great locations. One of them is right across Westminster Bridge from Big Ben.
Premier Inn County Hall.
Frequent poster here Mardee stayed there last trip to London and was quite happy with it.
Read some threads about the Premier Inns in London.
Let me find a couple of them, and I'll be right back to add them here to my post.

Edit: Here you go:
https://community.ricksteves.com/travel-forum/england-reviews/premier-inn-f415b5a6-ac53-4fb6-83a3-34f14ae6c4db
https://community.ricksteves.com/travel-forum/england-reviews/london-hotels-may-30-june-4
Mardee's review: https://community.ricksteves.com/travel-forum/england-reviews/review-of-premier-inn-county-hall-london