Like most people I have experimented with getting non-branded cartridges, but whilst they are sometimes much cheaper the quality varies and it always seems the cartridges do not last quite so long. So I went back some years ago to buying authentic cartridges. I normally buy the multi-boxes with all 4 colour cartridges, but overall the black cartridges tend to get more usage as I don't print out too many coloured documents or photographs, so I occasionally order extra black cartridges and this pack of three achieved a bit of a discount over the single cartridge price. I use the same cartridges in two printers in my two houses so it is really convenient to be able not to have to buy different kinds of cartridges for the two machines. Over the years I've had several Epson printers and several from other well-known brands and whilst Epson cartridges are probably not always the least expensive I have found their machines to be far less problem-prone and more reliable.