The HD600 might not deliver the slam or sparkle one might expect from a more colored phone.. but the HD600 offers excellent transparency and it's neutral-inspired signature does an excellent job of presenting the music in an 'honest' manner.
It'll sound especially great with that music. I like how electric & acoustic guitars sound on the HD600 (particularly with a nice tube amp). The HD600 has the dynamics to present orchestral music well, but it might not image as accurately or extend as deep (or high) as some other phones that might be especially suited for orchestral music. Though considering the HD600's 'chameleon'-like sound, it's never stopped me from enjoying music it might not be absolutely perfectly suited for.. even in those cases, it gets so much of everything else so right. For example, I find the ability to accurately portray the timbre of pianos somewhat difficult for a lot of headphones.. the HD600 does it with excellent tonal accuracy and transparency. Vocals sound very clear and lifelike on the HD600, too.
Speaking of transparency.. one thing that jumped out to me, when A/Bing the HE-500 & HD600.. was just how clear the HD600 was. It was frighteningly close to the HE-500 in that regard.. perhaps even exceeding it (palmfish could chime in here as he did an excellent, in-depth comparison of the HE-500, HD600, and another phone a few months back). The HE-500 certainly isn't the last word (or product) when it comes to transparency (the DIY T50RP Paradox is the most transparent phone I've heard to date), but as a $700 flagship product, the price tag is consummate with it's performance. For less than half that price, what the HD600 delivered in terms of transparency was truly impressive.