Would you recommend a similar setup to this ^ (usb dac with separate amp) as opposed to buying a more expensive desktop DAC with a built in amp? Right now I only have MDr V6 and Dt 770 80 ohm but I am planning to upgrade at some point to something more along the lines of an HD 600 headpone.
Not if portability matters to you. I use my DF with a FiiO E11 when I am traveling w/ my MacBook. It's a very portable setup that also lets me use the same E11 amp with my HTC One or iPod 5.5 gen. I like to mix it up with my gear so, for me, the E11 is all about flexibility and portability; oh yeah, and it's like $US 50 which is a great value IMO.
You can't compare the above with a desktop setup. Even my entry-level NuForce Icon HDP blows the portable rig out of the water - especially with the rest of the stuff connected in my sig.