I don't know, MaSu gripped me right from the word go, but I think you're probably right about the JnG OST songs being less hard hitting, probably so it wasn't too in your face while you play. As for this song, well it doesn't sound at all like Throttle And Mask now does it... ^-)
I dunno about the JnG OST. It seems like MaSu purposely restrained the music from being too heavy, and focused on SiD instead of guitar - which is not bad, perhaps it's good because it's game music. Maybe I'll just have to listen to it more to catch on, like I did with all of MaSu's music.