I installed the new printheads (all 4 colors) and printed two pages. But when I tried to print a third page, the printer would not print. The LCD display showed the printhead icons flashing, which indicates faulty printheads. I put my old printheads back in the printer, and the icons stopped flashing. I could print with the old ones. Then I put the new printheads back in, and the icons began flashing and I could not print. So I called Tech Support and they had me clean the printhead contacts, but that didn't fix the problem. Finally they offered to replace all the printheads free.
We have an HP DesignJet 500, that rarely gets used anymore, but works great for printing large scale assembly drawings for our warehouse assembly team. I'm unsure of the last time the print heads were replaced. I ordered a set of these to print out a bunch of new drawings. Everything worked great!
[This review was collected as part of a promotion.] It was easy to pop this in and resume printing immediately after the printhead was calibrated. The free overnight delivery helped keep the project on time, and the free eco-return was greatly appreciated.