godot I hated this (its really just bad Las Vegas showcase music) but like a lot of genres (metal, bluegrass, gospel), I don't have a clue as to why fans like it or what would make it an outstanding in its genre. So no rating.
My impression was that Jap chart music is mostly gap-toothed girls singing teen fare over over saccharine electronic pop.
My exposure to J-pop in the Western indie fan context meant something else entirely. Everything from Jap bossa(like Pizzicato Five and Qypthone) to Jap New Wave (Plastics and Polysics) was finds its way in.