Customer Rating: 
Summary: Good Cartridge
Comment: I have used after market cartridges at half the price, I have refiled toner in cartridges and tried to make them work, but on both counts have been disappointed, the quality of the print was bad after that. I am not sure if Brother is different but Original cartridges seem to work the best and the print quality is as original.
I will have to stick to original, despite the slightly higher cost.
Customer Rating:
Summary: Low capacity fixable, some may be defective
Comment: I was disappointed to find out that the toner cartridge stops working before the toner has run out. However, by obstructive the toner window on the cartridge with masking tape, the remaining print capacity of the cartridge is dramatically extended. I will leave it up to you as to whether you want to implement that solution or not.
I had another issue with toner build up on my drum unit from one of my toner cartridges. The problem was fixed by changing out the toner cartridge.
Customer Rating:
Summary: Best Value, Price and Service on the Internet
Comment: The TN580 cost a few dollars more than the smaller capacity TN550 cartridge yet it yields twice the output. By far the best value of the two. [...] offered the TN580 at the best price on the Internet and I received the item within a few days of the order. I therefore rate Amazon.com and their offering of the TN580 the Best VAlue, Price and Service on the Internet today.
I also rate the Brother 5250DN laser printer the best value duplex (2 sided) printer on the market. It has NEVER jammed or miss printed a single page and I've printed over 20,000 pages on it!
Customer Rating:
Summary: Brother Ink Toner
Comment: Excellent product and lasts a long time. This is the larger of the 2 sizes of toner cartridges and would continue to buy only this size. The quantity of toner is so much more than the smaller cartridges and for so much less money!
Customer Rating:
Summary: Product A+; Shipping UNSATISFACTORY
Comment: SLOW SHIPPING!
Product listed as "in stock", but took nearly 1 week to ship.
Summary: Good Cartridge
Comment: I have used after market cartridges at half the price, I have refiled toner in cartridges and tried to make them work, but on both counts have been disappointed, the quality of the print was bad after that. I am not sure if Brother is different but Original cartridges seem to work the best and the print quality is as original.
I will have to stick to original, despite the slightly higher cost.
Customer Rating:
Summary: Low capacity fixable, some may be defective
Comment: I was disappointed to find out that the toner cartridge stops working before the toner has run out. However, by obstructive the toner window on the cartridge with masking tape, the remaining print capacity of the cartridge is dramatically extended. I will leave it up to you as to whether you want to implement that solution or not.
I had another issue with toner build up on my drum unit from one of my toner cartridges. The problem was fixed by changing out the toner cartridge.
Customer Rating:
Summary: Best Value, Price and Service on the Internet
Comment: The TN580 cost a few dollars more than the smaller capacity TN550 cartridge yet it yields twice the output. By far the best value of the two. [...] offered the TN580 at the best price on the Internet and I received the item within a few days of the order. I therefore rate Amazon.com and their offering of the TN580 the Best VAlue, Price and Service on the Internet today.
I also rate the Brother 5250DN laser printer the best value duplex (2 sided) printer on the market. It has NEVER jammed or miss printed a single page and I've printed over 20,000 pages on it!
Customer Rating:
Summary: Brother Ink Toner
Comment: Excellent product and lasts a long time. This is the larger of the 2 sizes of toner cartridges and would continue to buy only this size. The quantity of toner is so much more than the smaller cartridges and for so much less money!
Customer Rating:
Summary: Product A+; Shipping UNSATISFACTORY
Comment: SLOW SHIPPING!
Product listed as "in stock", but took nearly 1 week to ship.