I have the RS-120 Sennheiser's on my night stand and use them just about every night and really like them. A real bargain.
I also have a pair of Koss Porta-Pros and for the money they are excellent, but I tend to use them less than my Grado 80s. Even my kids at school love the $99 Grados and are asking Santa for a pair for Christmas.
Now that my Focal Spirit Pros are broken in I really like them and they are the most expensive cans I own at $350, but my FAVs are still my 2 pair of AKG-K271s which seem to best match my 68 year old ear's reproducing ability. I will mix with the Focal's.