Even though I haven't played the game since I don't have a Wii U, I can tell that this has an amazing soundtrack. I love the remixes and the original composures, this is definitely the OST for you if your feeling bored in a rainy day. Although it does get boring after a while, but that doesn't stop Rainbow Curse from being a decent Wii U Kirby title.
This has to be my second favorite Kirby Soundtrack (#1 is Return to Dreamland). It has the constant feeling of nostalgia and joy until the final boss, where you remember your whole world is at stake if you don't finish the job.