Funny enough, although I have the Phonitor and HD-800 I have never tested them together because I have them in different places. But I did test extensively (and loved) Phonitor with Edition 8.
If the look is important to you, there is no match. Phonitor is a beauty, one of the most impressive designs I've seen in years. Its wealth of features is equally impressive, the crossfeed working wonders with Edition 8. It also happens to be the only SS amplifier I can use for hours without ear fatigue. But I wouldn't say it's the most transparent or detailed amplifier, especially if you activate the crossfeed. The sound is very natural, involving, easy on the ears but it's not the ultimate word in pure fidelity. On certain music tracks, especially high resolution formats, I definitely prefer to set most crossfeed options to off because there is a subtle but to me obvious penalty in SQ.
I have had V200 for a couple of months and used it extensively with HD800. They are certainly a good match together but, again, not the ultimate word in resolution, detail retrieval or soundstage. Once Weiss DAC202 was in the house, V200 went on sale. Comparing V200 fed from the DAC202's output to Weiss' own headphone amplifier, Violectric was deficient in soundstage, resolution, air but maybe offered a slightly better bass extension and a warmer signature. Trying Edition 8 on both, I definitely prefer the Phonitor. Unfortunately I can't tell you anything about HD800 on Phonitor.
