I think I like Spring Day a little more. Not Today is a stand alone, I guess - for me. It's very much a hype song. The kind of 'I don't know what's happening, but this music's grabbing on to me' music. But, there's not much chord progression - I DONT KNOW HOW TO EXPLAIN IT IN ENGLISH HAHAHAHA
But, the thing about Spring Day that got me was the bittersweet feeling it gives. It's a major song, but has a pretty sad meaning. And the DRUMS HOMAYGAHD. It leans more of a rock pop kind of thing. The composition is pretty complex but it's still easy listening. There's just a lot of Irony in Spring Day and also the anti-suicide message got me good.
i personally choose spring day. i just love love love the choreography, the mv, and just the song itself. i searched for the english translation and the song now has even more meaning to me now. ;u;
I love Spring Day when I can see the choreo, because it's just breathtakingly beautiful. But if I'm listening to the mp3, which is almost always, Not Today wins by a long shot, since I can't understand the lyrics and the music is bomb.