This theme made that game for me.
It reminds me so much of Ennio Moricone's work in the Man with No Name movie series (Fistful of Dollars, For a Few Dollars More, and The Good, the Bad, and the Ugly) that it added to the nostalgic feel of the game in a different way from the flashback screens.
And your arrangement of it using a guitar makes it much better, since it's not just a melody hummed by Sunny. You have my head bobbing in approval.
~Joshy676