Great price on Amazon, probably the cheapest you will find. usually 10.99 elsewhere.
Cost you more in argos for 2 cartridges at 7.99.
If you buy 4 packs this still works out cheaper than the 12 cartridges on Amazon currently on sale @ £29.95. buy 4 packs of these for only £28.72 and get free delivery too!
You will need to buy at least 3 packs to get free delivery. still a good deal though.