Denied refund for keyboard causing injury

So I bought a Logitech Wave Keys keyboard online, used it for less than 2 weeks before it started causing pain in my hands because some of the most-often used keys are on odd places and it was difficult to get used to because of it. I boxed it up - still in absolutely perfect condition - put it in my car to return to Computer Mania in Canal Walk and forgot about it. Eventually (just under 3 months since it was delivered) I returned it and was told that I'd get uphill from head office, which I thought would be odd seeing as the product is in perfect condition (for some reason the staff member that logged the return add "general wear" to the note.... say what? It looks as if it was just unboxed!). So they call just over a week later and say I can fetch the keyboard as they won't be doing a refund. I found that unacceptable and called the operations manager who was rude and started talking over me, laughing and saying that he's been in retail for 30 years, that he knows the CPA and that he's going to end the call and that he won't be refunding me. Really now. So I ended the call first, regrettably with some colourful language (my apologies).

Being a developer, I have to use a keyboard for many hours every day and cannot risk permanent injury to my hands. The keyboard is not suitable for the purposes for which it is intended and fails to meet the standard of being reasonably suitable for its intended purpose - which is covered under the Consumer Protection Act, but I was told I'm completely mistaken and refused a refund. I have no doubt that the Consumer Commission would agree were I to escalate the matter to them. Which I might. So now I will be stuck with a R1,400 keyboard that I can't use because it causes repetitive stress injury in my hands. The more expensive, regular size Logitech keyboard that I purchased from Takealot is much better suited to large hands. But just because of this issue and ill treatment we won't be buying anything from Computer Mania again. Takealot would've taken the keyboard back without question. So our businesses will be purchasing from them from now on. Goodbye, Computer Mania.