I use and trust Headphone.com(Headroom), as a very complete review source. If it isn't on their site, it is probably not worth worrying about. My Senn HD650's are still great after all these years, I've used them for everything from playing my Roland V kit, joyous listening out of the RME Babyface, and of course practicing with the Carvin MB12 late at night. Grado has a particular sound, some like others do not. Test Grado before you buy to determine where you fit in the spectrum! I like them fine, though of course do not own any. Most headphones will love the extra kick of an amp, you will too.