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Xerox Phaser 4600DN (~$1010-$1050) High volume, solid workhorse, doubled-sided, letter-size, black and white printer. This is now an old model and becoming harder to find.
Last checked on Amazon:
http://www.amazon.com/s/ref=nb_sb_noss/190-4469090-1987617?url=search-alias%3Daps&field-keywords=xerox%20phaser%204600%20dn
Xerox Phaser 4622DN (~$1100-$1300) High volume, solid workhorse, doubled-sided, letter-size, black and white printer. This model replaces the Phaser 4600 line.
Last checked on Amazon:
http://www.amazon.com/Xerox-4622-DN-Monochrome-Printer/dp/B00JHK3TFC/ref=sr_1_1?ie=UTF8&qid=1447690752&sr=8-1&keywords=xerox+phaser+4622dn
Review here:
http://www.pcadvisor.co.uk/review/mono-laser-printers/xerox-phaser-4622-mono-laser-printer-review-3523020/
Xerox Phaser 6500DN ($350-$400) Color double-sided letter-size laser printer. Not as heavy duty as the Phaser 4600 for high volume printing so don't use this printer for high volume.
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