I stayed here on a business trip recently, as a where I usually stay in Seoul was full. The location is brilliant, the service is amazing. The only thing that would stop me from giving this 4 or 5 stars is the 20,000 WON charge for 24 hours of internet.
One of the things South Korea is famous for is it's technology and when you are on a business trip, you need internet access. Not offering free internet, even in the common areas, such as the lobby or a business center is inexcuseable for me.
Other then that. It was a great stay.