I used to have a Xerox phaser 8400 solid ink printer, gave fantastic looking photos even on standard A4 paper and would happily take 3rd party inks as the ink itself a wax block with no electronic parts. Unfortunately it was quite a hefty beast and really requires its left on all the time as its warm up takes a while from cold so i eventually sold it to a local business as i very rarely used it for colour prints and a small Kyocera desktop mono laser was a cheaper option.
Looks like Xerox may have stopped producing solid ink printers now, as there are none showing on their website