If you want revealing go with KGSS + 4070 instead. Those things rule. If I could have found a pair of 4070 for a reasonable price I think I may have kept my KGSS but for me the O2s weren't it.
For me the 800s + GS-X are pure nirvana, I think they are as close to a wire with gain as anything I have ever heard. I love them, I don't even do any wild ass math or equalization on them.
That said if you really want to hear the differences between dacs something with a hotter (rather than neutral) high end is probably in order.