Just got my RP-21's from lostspyder today and they sound awesome. Nice and accurate and just the right amount of bass. Thing is nothing has impressed me more than my KSC75's. For the price are one badass pair of headphones. I also got a pair of senn hd212 pro's from her also. They arent the best... to much bass imo. So they might be for sale sometime soon... also might be getting rid of the ms1's just for a heads up. I think the rp21's are a little more my style, but I need to do a real close comparison sometime first.

how would you compare the RP-21s to the MS-1s?

Im still a little unsure... give me a few days and Im gonna do a good side by side comparison and let everyone know, I can tell you that these cans sound great... nice and clear great clean bass... but time will tell