I have an old HP LaserJet 1022n that keeps working despite all these years of heavy use. I got tired of paying Staples a fortune for a "genuine" HP toner, so I tried this far more affordable alternative. Works as advertised, no problem with compatibility. I'm not sure if it lasts as long as the HP version, but it lasts quite a while. I always keep an extra one in reserve.
PROS: No problems noted.
CONS: A recycling option would be nice like the one HP offers with its toners & inks. I hate to toss it in the trash.