Just got the HD700's for my B-day (best wife ever!), and all I can say is they sound INCREDIBLE. Listening to Beethoven Violin Sonatas (Leonidas Kavakos) - the realism is eerie...just pure music making, like "you're there" feeling. I never got this with my HD580's. The rendition of the piano is so clear and tuneful. The violin sounds exactly like it should (I should know since I play the violin). So far, with a few hours of listening, I'm one happy Birthday boy. BTW, source is Musical Fidelity V-DAC II with V-PSU with Burson Soloist as amplifier - super detailed yet not at all fatiguing and I haven't even started burning them in!!!
Congratulations! Some believe that the HD700s have much better sounds than the HD800s. Price wise, excluding the lowball prices last night from Amazon on the HD800s, the HD700s appear to be a very good value compared to the HD800s. Plus I have heard that the resale value of HD800s are not as high as the HD700s when looking at resale price percentages of the original new headphone purchase prices. Both are known as very good headphones. Say thanks to your wife a few more times!