I have the HFI-780 and have quite a hard time coming up with faults. I "upgraded" awhile back to the Shure SRH 940, but ended up selling the 940 as I felt the 780 had a clearer more forward sound with better bass control.
I wrote a review that you might find useful: http://www.head-fi.org/t/628344/5-way-mid-fi-comparison#post_8714358

















