Choi Ji-woo's dress complements her features and silver looks good on her. :) And the effort she exerted in choosing a dress that would make her feel look good is something people should appreciate. And don't take it on her that she chose an expensive dress to wear at a very popular award ceremony (she used her own money anyway).
Kang Sora chose to wear an inexpensive brand which complemented her figure (as her agency has defended her why she chose to wore that dress) - which worked for her. It also made fans think "Ah, even with an inexpensive stuff one can still look good." :)
They both chose what they wanted to wear. So why are you people making a big fuss out of it?