Where would you stay ? Iteawon ? In Hamilton Mall at Iteawon Street they sell a few cheesy watch not worth buying, but the ladies would love it....germstone and bling bling
At train station there is one mall. They sell quite a number of Grand Seiko.
At the airport also got a few nice shop selling watches
In dongdeamun, city famous for shopping, I cant find any watch shop, same goes for namdeamun, and one place i cant remember the name , suppose to be the IT mall ...cant find any decent watch shop