I don't usually review movies, nor a trilogy in this case, but I truly believe this should be an exception. I'm probably like most of you, viewing this boxset after watching Oldboy. However, the reason I bought it in the first place was to have my favourite out of the trilogy in blu-ray; Sympathy for Lady Vengeance.
Just as a general gist, these films are not narratively connected at all, though all tell profound stories in their own right. Mr. Vengeance being the most gruesome one, Oldboy being much more bitter, whilst Lady Vengeance being surprisingly elegant and detailed,(despite scenes of murder/torture).
As a note, this version of Lady Vengeance is the Fade to Black and White version, of which does what it says; as the movie progresses, colours will eventually became shaded white/black until only subtle primary colours remain. Albeit I was rather disappointed when I found out the colour version was not included, but after now watching it the second time, I personally feel this is the version Park Chan-wook intended, and in my opinion is superior to the former.
Nonetheless, as a fan of contemporary Korean movies, I am truly happy with my purchase, especially with the current price which I had purchased it for, it is an absolute bargain!