I got the HDVD 800 to go with my HD800. I don't know how it would do with Oppo phones. Perhaps Oppo phones might work better with an Oppo amp, keeping everything in the same camp like I did. I know the previous Burson, the HA160D did not work especially well with my HD 800s or my 600s either. As I see it, it's all about synergy; What things work well with each other. The only way to really find out is to put stuff together, put the phones to your ears, and let 'er rip. Your ears will not lie. May take a while, but you eventually will find your own truth.
My only comment before concerning the Oppo 103 was that now that one has great phones and great amp, you now will be limited by the quality of your source. You may well get what you want canwise, and ampwise, and pursue the quest even further for a better DAC, or other source.
Good luck in the never-ending quest.