Drag:
You could give bleekers a call...although I dont think they have that much...they didnt even know what HD280s, 580s or 600s were.....well at least the one I called didnt.
If you're going to be listening to your MP3s with headphones that you're going to buy...why not audition the headphones with MP3s? Isnt that the logical way?
I mean if you're never going to be using your headphones for listening to 10000 dollar stereo system why bother auditioning them with the 10000 dollar stereo system. That's why Omer will let you bring home the Cans to listen to whatever you like and use them the way that you are going to be using the cans that you're going to buy.
let me put it another way...if you want a vehicle for offroading...you wouldnt test drive a hummer on a smooth oval race track would you? No, you would take it out into the bush to see if it was a good as a Land Rover or vice versa....same thing here...
I bought my Koss UR40s for work so I left them jacked into the CDROM at work for a week and listened to them at work...the box is still here in my cubicle. I borrowed the Senns and AKG to listen to at home so I brought those home and listened to movies and CDs on my Onkyo, music on my MD, and played MP3 and games on my SB Live...audition them
Trust me before you call bleekers to call Omer and see what he has in stock that he can lend you...(sadly his website doesnt list everything...) He has lent me speakers, receivers, cables, headphones, etc...with no obligation...
Regarding headphone amps, he can get the XCan V2, and rega ear headphone amps which sound amazing...again call him up or email him and ask him.
oh and did I mention his prices include the double tax...
so what you see as price is what you pay...and what you get back if you decide to trade them in for something new or something better...
good luck