Even I stayed on a Tuesday night, music from a bar was quite loud until 3am. Room was pretty dark, not even much lights from room itself, so not very convenient if you have to work, ended up going to the coffee shop next to the hotel for some work.
Area is great if you need to go to kintex exhibition center, 5 minutes by taxi and around 30 minutes walk.
Even you are far from downtown Seoul, the area has everything you need.