6 months of starvation, here I come! (Just kidding, been thinking about them for long)
HD600 were certainly a bargain and these are keepers whatever the preference, they're just too valuable. Plus I get to hear how elements come together in mixes quite well due to narrower soundstage. I have a feeling both would complement each otber.
HD800 for crisp accuracy and soundstage, and HD600 to make sure my mixes are not too warm due to HD800 thin reproduction (me adding extra thump where not needed).