I think you should see if you could test them all.. Seriously though the XB500's are the funnest. But I honestly could NEVER listen to them for more than an hour, 2 tops. The M50's I love. I mean seriously they are perfect.. They are so balanced but just that BIT of extra bass and it makes it sound PERFECT. The XB series will overdo you on the bass. Definitely. The Shure's I'm not sure about at all. But if the guy is telling you to get them and hes tried all the headphones out. Who knows, he might know best. But honestly bro I mean bass is great, your head thumbling is a great feeling. But it's not going to feel good after an hour. The M50's have that PROPER bass so it isn't TOO MUCH. Honestly I wish I could have one of all types of these headphones and switch them from song to song. It's a plan of mine anyway.