I recently traded in my ps500e's for the 700's after auditioning them 4 times (I will never judge something on one audition again) and being offered a great price for both. The treble spike is no joke but with the 500's I could only enjoy maybe 60-70% of my music - with the 700's I can listen to 70-80% and it's A LOT more fun, especially with drum and bass and classical they blow me away with every use and I rarely hear sibilance on good quality recordings - I look forward to using them every day and actually prefer them over the hd800's for any kind of fast music. The soundstage and imaging are stellar in my opinion and minus the treble spike I feel I'd miss out on a lot of sparkle, ala Grao tonality that my 650's lack.
I'd planned on travelling quite a way to audition the LCD x's and 3's for my BIG buy, but after hearing this news I'm very, very excited.
In short: I think you sold them prematurely and I think these headphones get overlooked