It's a shame some people have some build quality issues, but I'm immensely happy with my GR07s. With over 300 hrs on them, they actually sound more sibilant now than before (I think it's because I keep turning up the volume more and more) but still, they spank the hell out of my cheapies the Superlux 381F. The 381F is no slouch for a budget IEM, but the difference is night and day when switching between the two. Even though it's not really a fair fight, the instrumental separation on the GR07 is far superior, the timbre is far more realistic, and texturing/layering makes the detail feel so much more satisfying. I also use the GR07 on a much more regular basis than my DBA-02 that I've loaned my DBAs out to my friends for an extended period.
The GR07s just have gobs of detail and control, and even though some people may feel it's a little boring, it's also that attribute that allows it to be so measured and composed. I don't mind the broad treble 'spike' and I also think it matches very well against the FX700. They're very different IEMs in nature, and I personally find the GR07 to be more enjoyable. I guess I'm just a more analytical listener.