The only negative I can say about replacement toner cartridges is that the handle that is built into the cartridge to make cartridge removal easier is set back so the finger grip hole is down and not up. This is a minor issue, but it does make it more difficult to remove the replacement cartridge when it comes time to replace it. TO UPDATE. I get a "CANT DETECT" error message indicating that the toner cartridges are NOT detected. Brother support says this happens all the time with non-Brother 'counterfeit', 'compatible' toner cartridges and that I should replace it with a Brother toner cartridge. As you can see in the picture, the toner cartridges are recognized as almost full, but one of the contact points that indicates the presence of toner is not touching.