This is a video of me, Tasselfoot, beating the 40 Inferno levels of Perfect Balance. They're definitely harder than the Harmony ones, although most of them still aren't too bad. And the ones that are usually are only hard because you can't place blocks in the gray area at the top.
Game: http://www.kongregate.com/games/ttursas/perfect-balance/?referrer=Tasselfoot
Music: Kick Your A by SuperGreen X. http://www.sgxmusic.com