Hey guys.. Anyway you might remember me from my other headphone thread... Anyway I am ready to buy the headphones now... And I was pretty much set on the Sony MDR-V6 when one more set caught my eyes, the Sennheiser HD515.. Anyway thoughts on those headphones? I am using them either on my computer or mostly my iPhone 3G Are they worth the 40 or so $ over the Sony MDRs? Thoughts?