Originals are better if you are a collector and you want the physical copies, but sometimes the collections could be better than the source because the high resolution, remastered sounds, extras like documents prior the release of the game and such, or the always helpful save states for people that never beat those games at the time.
If I can have both, I am fine with the idea.
Maybe I should mention that sometimes those collectiones include input lag and sound issues, if the issues are almost impossible to note for the average player, I have no problems at all.