Why I will never buy electronics from incredible connection.

I I went to incredible connections in gateway down in durban to return their faulty laptop. When I bought it I was told it will work at normal speed only for the laptop to be terribly slow while brand new. I requested to return it or make an exchange and I was told I have to pay 15 % of the cost price for a laptop I returned within 7 days. That is so ridiculous and I told them that this was not communited to me when I bought the laptop because that would have influenced my decision in buying from the store. I just want my money back and I don't see why I have to pay any fee when I'm return in their goods that's not functioning in the manner that was expected. This has put me off to buy anything from incredible connection's cause they make you pay for their shortcomings. I would rather purchase my electronics elsewhere