Jim McCarthy
Google
I've been fortunate to have stayed at quite a few excellent hotels around the world, and the JW Marriott in Seoul is the best service I've received anywhere. All of the staff -- the bellhop, the check in people, the room service, the cleaning woman, the laundry people, the cooks and servers and restaurant staff -- were remarkably kind, attentive, and accommodating. I don't think I've ever experienced faster service, either.
Thanks to the following people, from the 9th floor Executive Lounge:
Ms. Hanoka, Ms. Daisy, Ms. Olivia, Ms. Elle, Ms. Ellie, Ms. Min, Ms. Rudy, as well as Mr. Heyun (spelling?) and the tall chef (Mr. Sung).
The 9th Floor Executive Lounge has an large, excellent variety of dishes for breakfast and "happy hour" / dinner which rotate daily. If you feel like Korean food, there's plenty. If you don't feel like Korean food, there's also plenty. There is a decent selection of wines and liquor to mix your own drinks, if you'd like.
As for the location -- you could do a lot without every going outside, because the hotel is directly attached to the large Singhae shopping mall, as well as the Express Bus Terminal -- which has bus and subway connections to all of Seoul and beyond.
I also enjoyed the Marquis Spa, which is one of the largest gyms in Korea (I was told). I had a fabulous body scrub.
The overall experience -- spa, gym, executive lounge, rooms, location, and staff made for a wonderful stay.
Gamsahabnida!