I love, love, love Days so much! One of my favorite songs and PVs~
I also like the orchestra version, and I'm not huge on orchestra versions. And the 8-bits of Tears remix, I love that, too! It gives it a bit of a different feel. I remember when I first saw the Days PV, I cried so much.
I was like, how could you do that to Ayu Shu-ya!? XD