I have a pair of Grado RS1's and love them for all sorts of music. They're great for rock, blues and classical although I've never done a direct comparison to Senn's I can't imagine being disappointed with them for any type of music. I've got a nice set of 3rd party circumaural pads that make them alot more comfortable and to my ear really improve the sound. Paired to a headfi amp this has been my listening station for the last few years... soon to be replaced by my yet-to-be-delivered axiom setup. Although I'll actually keep my listening station in my office for unobtrusive listening sessions
The RS1's are a bit of a different animal...once you get up in higher end grados they get a lot more balance to them. I wouldn't mind owning RS1's eventually, or their counterpart Alessandro MS Pro's.
Never give up on headphones, you'll never get the detail and intimacy with your music unless you drop tons and tons more on a speaker setup.
