^ cmon, don't give the guy a hard time. I agree it's hard to compare the two, as one is an IEM and the other a over-ear, but he's just looking for advice.
I vote for the SE530 actually. The SE535 has fit issues for a lot of people. The SE530 goes way deeper into your ear-canal than the SE535, and a used pair is probably cheaper. The only problem is with the cable (which isn't detachable); however, you can get them custom-molded into cIEM's like I did with a detachable cable for about $120 USD.
The P5's I have are among the worst headphones I've ever owned (despite looking cool), but I can't really comment on the P7's b/c I've only briefly demoed them at an apple store. The C5's are also horrible. B&W should just stick to their great speakers.