The transparency and clarity screams on FX-700. I have yet to compare my Etymotic to the FX yet, but it's better than IE8. Timbre on FX-700 is superb. But I have not heard the SE530 before. Isolation on FX is not that good, but I can almost assure you that the FX should be more natural than SE530 in terms of reverb, soundstage and tonality, due to the open air design and the wooden housing. Anyway, both are good choices. My friend has Shure, and I prefer the cable on FX-700/IE8 (both are very similar, softer and not as stiff as shure's).
Oh, regarding the isolation on FX, i'd give it a 6-7 out of 10, since it's open air design. If you're aiming for utmost isolation, FX might not be suitable. Shure with olive easily has better isolation. The FX does leak a bit of sound out to the environment.
People said things like treble roll off on SE530, and personally I do not want to comment on this, but I can comment on the FX. The treble is prominent, and there's shimmer and sparkle to it. It's not harsh or sibilant in any way, even though it extends very high up. The bass is tight, and does not overpower the rest of spectrum. It is not that kind that slaps the music on your face. As far as I can recall, FX is more natural than MD and IE8 that I have, and the bass on MD extends the lowest. IE8's bass lingers the longest. FX is just about right for me. Check out the impression thread of FX-700.