I wanted to post here and then I realized I don't know what would qualify as guilty pleasures (music pleases me or pleases me not, no guilt involved), and the best I can think of (music that may not pass my usual criteria of quality) are all relatively similar (kitsch or over the top or baroque-popy, that type. Similar!).
Buut! I found two good ones:
This following piece is my definition of bad taste in music. It's... dreadfully bad in my criteria. However, I find it to be great roadtrip music! Energetic and loud and sort of funny??
And this one, which I suppose is different enough to qualify.
I don't find it bad, but it's really not in my usual tastes, and I love it: