OEM toner cartridges are great in quality, but really high in price. My friend told me maybe I can choose compatible ones, but the quality cannot be valued before using. I have never used a compatible toner cartridge, do you have any good suggestions? Thanks a lot.

In my opinion the dangers of using non OEM carts is not worth the potential savings. In my experience it's a 50/50 proposition. About half the time it works and half the time it can screw up your printer.

There are two possible definitions for the term "OEM":

1) Original Equipment Manufactures.
2) Other Equipment Manufactures.

With respect to toner cartridges, other equipment manufactures really just refill most cartridges. In some cases that is fine, providing the "refill" is an exact chemical match to the manufacturer's product. However often time it is not and results in poor print quality issues because things like seals are not also replaced.

Where the cartridges also contain imaging components, just refilling the toner does nothing to rejuvenate aging components with these cartridge assemblies.

Best bet is to stick with the "Original Equipment" manufacturer that way if there is a problem, the cartridge can be warranty replaced. If you use a refilled cartridge you are on your own and if the toner spills into the machine, the costs for repair and / or replacement of the machine are all yours.