I just got my X10s, and I must say I think they are amazing, for what they do. I own the PFEs, sleek audio sa6, kilpsch s4.
Overall, the X10s sound signature is nice and warm & a good amount of bass. The X10s cannot compare to the PFEs or SA6s in terms of clarity, they can't handle the highs all that great either, however they are soooooo comfortable that I'm alright with the trade-off.
The S4 had way too much bass, these things were too much and super uncontrolled.
The PFEs are the clear better phones and can extract every ounce of detail in all of my songs, they are not too far comfort wise from the X10s, but they are harder to put on than the X10s.
I can truly say that the X10s are my new favs because I can't even feel they are there. *set em and forget em*
These phones are a compromise, comfort over sound, but they don't sound bad by any means. They have a very relaxing sound with great isolation.