Hi,

I had a one night paid stay at this property.

Location: Located right in front of Seoul City hall and square, it is very well located especially for first time tourist and even repeat visitor to Seoul. There is a metro stop just outside of the hotel, but basically you can walk to different attractions within 2 km of the hotel radius. Close to the Namdaemun market area.

Check-in: Initially approached the front desk for check-in, but upon knowing that I was an Elite member, was escorted to the lounge (18th floor) for check-in. Fast and efficient check in with a run down of the benefits at the lounge.
Was informed that I was "upgraded to a room with a view of the plaza and the nearby Palace.

Room: A corner room with a close to 180 deg view of different attractions. (becareful this can be an issue if you are too sensitive to noise as it faces traffic, the occasional protest marches, and other street noise) - which I had no issue with and they normally ended by 10pm. Room was very beautifully decorated - a modern twist to the room which was functional (might not be a taste for all). Size was OK - though I had the Premium Suite room reserved. I did have a peek at the normal rooms and they are small. I do not really agree to how they categorize the rooms, as mine was far from being even a mini suite. I would say it was more of a Premium room - which would have been a better categorization. There seem to be a fireplace that can be used during the winter months. TV channel options were good and the bed was very comfortable. There is a tablet like control for everything in the room. One unique feature not seen often, is that the curtains will automatically close and open when the key card is removed when leaving the room.

Bathroom: Not very large and might even be too small when 2 are in the area. Functional with a walk in shower or bathtub (again on the smaller side). There is the Japanese/Electrical type toilet which is a smart one - flushes every time you have use it (you need to sit on it). Toiletries were from Hermes (not sure if this is only for Premium rooms).

Executive lounge: The lounge is not very large, in a long type of layout instead of a larger square type layout. There are different small spread between the main meal times.
This is where in my opinion as a 5 star hotel, failed miserably. I was warned of how busy it will be, and therefore, they tried to avoid this by splitting the evening session into 2. I selected the 2nd option and even that, arriving at that time, no proper table was available and lots of guests turned away and requested to return later or they will call their room. I opted to just sit at the couch area and shared the area with other guests. This is situation is still understandable, though they should not sell so much access or arrange a better arrangement if they know they will not be able to cope (e.g. let guest with access to have other options at other F&B outlet of the hotel).
However what was totally unexpected was the quality of the food - a total failure. I do not know in which country are chicken nuggets, cheese sticks and just plain pasta covered in tomato sauce seen as a quality meal fit for an executive lounge. I can understand that they will need to do fast food refill, but just serving those items in the lounge is just not acceptable unless you are at some fastfood chain or some children party. Did not bother to complain, but just could not believe my eyes.

Breakfast: I had this in the lounge which for me was a good selection of Asian and Western choices.

Staff: In general, as expected all staff were friendly and helpful especially with the crazy service charges in Korea. (that is why tipping is not needed in Korea)

Gym/Spa/Sauna: These facilities are located in their annex building - I guess some people will feel this as an inconvenient especially during the winter months where you need to get out of the hotel cross the street to the next building.

Elite benefit: As a Plat, upgraded to a better room with a view, given lounge access, one free clothing item per day laundered, late check-out. As stated by others, if you want to have breakfast at the restaurant, you will have to pay extra.

Generic: In general, not too bad of a hotel. For the price/quality paid, I would say it was slightly on the expensive side especially the size of the room and quality of the food. I would actually give this hotel a 3.5 rating based on my experience. However from location point of view, this would still be a good choice in Seoul for a luxury hotel.

Cheers!