If I did not know better, I'd say that we have come a long a way and @Lucky may be 'warming up' to Hilton and HHonors. Congrats on scoring a suite upgrade!
I am now in Seoul, SK, on the 4th night of my 5-night revenue stay at Millennium Seoul Hilton (strangely named since typically Hilton properties are typically named with 'Hilton' preceding the name of the city or location). With YUGE columns, a spacious interior, a great architectural design, 5 restaurants (Italian, French, Japanese, Chinese, "International") on the property, and a great location near touristy Itaewon district, this is one incredible Hilton property. In my opinion, this Hilton dwarfs Park Hyatt Seoul, where I stayed a couple of years ago for 5 nights, in almost every respect. Of course, it does not hurt that I was upgraded to a suite here as a HH Diamond, whereas at the PH I had no such luck as low HGP 'Platinum'.
There is Grand Hilton Seoul and Conrad Seoul, which I may check out in the future (likely just the Conrad, as the Grand Hilton does not seem that 'grand'), but in the mean time I wholeheartedly recommend the Millennium Seoul Hilton. As icing on the cake, one of the city's top casinos, the "Seven Luck Casino", is right next door!
Cheers!