I shall take your word for it and purchase the 750s then, thank you very much for the help!
Edit: Might I ask how long of a burn in period do they need and what way I should burn them in? Could I just put an iPod on shuffle with them at normal listening level or should I put em in an amp?
About burn-in, you should get stable results after 60-100 hours.
While many Ultrasones already sound acceptable without additional amplification, I strongly recommend you to get a headphone amp, like a PA2V2 or a Fiio E11. I recommend the PA2V2 over the E11, it has more driving power, the battery runtime is 10 times longer (100h on the PA2V2 vs ~10h on the E11), and the PA2V2 signature pairs up nicely with Ultrasones.
EDIT: Basically, Ultrasones can sound ok without additional amplification, but they scale up very well with better gear, both better sources and amps making them sound much better.
Edited by Roller - 12/6/12 at 2:37pm