I don't have any experience of either of these companies, but I checked them for cartridges for my HP Deskjet 959c for which I use C6578A and 51645A cartridges. inkjet-cartridges.co.uk insisted on offering me compatible cartridges, I could find no way of getting to HP originals. valueshop.co.uk were very similar in price to my usual supplier, 7dayshop.com. They were 15p more expensive or the black cartridge, but £2-40 cheaper for the tricolour. Their postage rates are a little strange. If I order the cartridges separately, each bill will be under £50, and so postage is free. If I order them together, the bill is over £50, and so I have tp pay £3.95. From 7dayshop, the postage is £1.95 whatever the quantity, as long as I don't mind waiting a week for delivery.