Usually you will find that a printer of good quality should last more than 15 months, there is something within the consumer laws which allows for this.I have a HP 590 OfficeJet which is now about seven years old, and as never failed in all that time. Have a word with your local trading standards on that subject. Some printers are not cost effective in seeking a repair, and this may also depend on the manufacturers policy, as some manufacturers will just replace the whole unit.Stores like PC World usually really on the manufacturer for repair and service backup, as this is the best and quickest way in obtaining a replacement or repair.
I recently purchased a fully working brand new Dell [Lexmark] printer for £9.99 which included delivery. At that sort of price,the warranty must have been worth more than the printer.