Thanks Pandora. PM me when you need tyres, I'll see if I can hook you up with someone decent, or offer any more advice when the time comes.

OLP; They're not really similar in size... Mazda6 come with 205/60r16, 215/50r17, or 215/45r18 (according to a quick web search, have my full tyre listing at the workshop still). The Mickey T's are a light truck rated tyre (LT tyres are also usually sized in the imperial), and just, well, bigger. Google the image of the tyre that Beckoes has, and compare it visually with your tyres. On paper, the sizes may look similar, but they're not really.