When someone has the cash to splash on a R3600 case, I'm pretty sure saving R184 won't matter to them. Otherwise the price differences are not really huge except for the Graphite 600T.
And as I said in my other post you need to take shipping into account also, maybe then it would matter. Unfortunately the shipping costs can not really be done on article.
Last time I checked Landmark Pc has the most expensive shipping costs because you need to pay separately just for insurance, most if not all other online stores include this in their shipping fees.