Worst product and warranty service I have ever experienced

I purposely went to Dial-A-Bed and purchase an expensive "quality" product because I thought it would last. in 2011 I paid R9000 for a bed which costs R14,000 today. with in 4 years of buying the bed it started to develop a sag on the right side which got progressively worse and is now a hole on the side. I contact dial-a-be d who refered my to the manufacturer Sleep World who sent out an assessor of sorts. He sent me a quote for R4,200 to repair their faulty product. I can get an expensive replacement for R5,000 for a brand new mattress. I am told that the warranty work on the percentage of time from purchase times the current retail price of the bed. In other words the warranty means nothing. It has no value and is a FALSE promise on a defective product.