Recently traded in my ER4P's for ER4XR's. Initially they were too bassy as I was used to the 4P but over time, I think my ears have adjusted and it now sounds better. Sub-bass definitely seems accentuated which is appreciated for certain types of music. All in all, I think it was a fair purchase though the $350 is relatively steep.
Unfortunately, I've only had these phones for less than two months and I'm already having cable issues. When there's any type of tug on the cable, I can hear the left channel cut in and out intermittently. Did some feeling around the cables to see where it was occuring and it seems to be the location where the cable goes from one line and splits into two channels (the "Y"). Any slight pull at the bottom of the Y leads to intermittent sounds. Any thoughts on how to resolve this? I went almost 2 weeks without headphones when I traded in my ER4P's for the coupon code to get the discounted XR's and don't want to go through that again!