Yes, fair point! Though (as someone alluded to above) I would always pay the extra few pounds for the convenience of dealing directly with BA in case things go wrong. Not that BA's customer service is always great, but dealing with a middle man is almost always worse, especially if it's some bloke in a basement in Hounslow who may or may not answer the phone (which is what you often get through Kayak). Finally, if you have a BA Amex card you only get your double Avios if you spend the money directly with BA.