Fair enough.. Although you realise that tiles will suffer WELL BEFORE a colorbond roof will. Tiles are not a great idea in Australian conditions. They are terribly impractical, hold the heat in summer, require a lot more maintenance, fade, crack, if (or more accurately when) the sealant fails you'll have leaking, colour fades. They are also very, very heavy and put unnecessary stress on the house.
I do understand that some people prefer the look of tiles, personally I'm a fan of the modern or contemporary style, so much prefer a colorbond roof. Not to mention the 'green' advantage. Colorbond reflects heat and cools down extremely fast once the sun goes down. Plus it's a reusable product, which requires less energy to manufacture.
Well, I know our house will have trusses to deal with the weight of the tiles. Also, I think what a lot of people forget is that when they say they've had tiles for 20 years and they were horrible, those are 20 year old tiles. New tiles are a lot better and made to withstand this sort of stuff, which is why you hear of people who have had their tiles for 4-5 years say they haven't had anywhere near as many problems. Just my 2c. It's an individual choice, and to each their own.
Saint Mike, unfortunately, I do think CB will date. That's another reason why we chose tiles, it's classic and timeless.