Yep hplj 4, 4+, 4M, can last a very long time. the insides are made of STEEL. only plastic is the pretty surround.
I used to service these printers so I've seen them with 300K, 450k, pages printed and pair from a big company's HR department which still printed their own checks that had 1million +copies EACH. Minor issues of jamming every 4 or 5 hundred pages, a little crinkling. Easy to fix, one just needed a new roller kit installed and the other a new fuser and roller kit.
Comment from one hr lady was I could have the printer when I pried it from her cold dead hands. The other one wanted to take it with her when she retired. (they actually let her)
BTW HP DOES NOT make these printers! Cannon did and for some models still does! I beleive the cannon lp-430 is the direct model number. Internal parts even have hp and cannon part numbers and aprt from some circuit boards and the outside plastic molding everything internally is the same.
I wish to see things not as they are but as they should be.
Main machine: Core I7 -2600K @ 4.5Ghz / 16 gig ram / Radeon 7870 / 240 gb Corsair ssd / 5tb hd
Old machine: Core 2 quad Q6600 @ 3ghz / 8 gig ram / Radeon 6870 / 240 gb PNY ssd / 1tb HD