Aside from the recommended site posted earlier...I have the 650's. I'm surprise you prefer Senn's over Grado's...most rock listeners like the Grado brand for their bass/mid bass slam. I love my Senns but mostly for their detail...I sold a pair of Grado's that I wish I kept for listening to rock.
I've heard good things about the 595's but haven't listened to them directly. I agree that the 600's are the best bang for the buck. I too am using MF's X-Can V3 that controls the hard to drive Senns nicely. Be wairy of any headphone jack on components (even name brands) they are usually junk that is thrown on...Cary being one major exception. If you are getting an amp consider Ray Samuel's amps...I would have bought one if I didn't already have the MF.
I've heard good things about the 595's but haven't listened to them directly. I agree that the 600's are the best bang for the buck. I too am using MF's X-Can V3 that controls the hard to drive Senns nicely. Be wairy of any headphone jack on components (even name brands) they are usually junk that is thrown on...Cary being one major exception. If you are getting an amp consider Ray Samuel's amps...I would have bought one if I didn't already have the MF.