Let me share the one bad experience. The company was using a refill "service" and they supplied a BUM drum. The drum didn't turn.

What happened next wiped out all the projected savings.

The gears in the printer stripped, jammed and the drive electronics failed. Since HP service was called and they found the refill cartridge, no warranty was in effect and the repair bill was nearly the price of a new printer.

If you get some toner and DIY this, don't overuse that cartridge. Toss it out after a few fills.

BEEN THERE, DONE THAT. PAID THE PRICE.

Bob