Gutters and tanks

Dear lazyweb, we've just got a quote for some Colorbond guttering to replace the rusted-through guttering on our new house. I'm exploring other options, given aluminium and PVC don't rust, and shouldn't be significantly more. There's also guttering systems that keep leaves out and don't require clearing. I'm thinking it might be worth combining this job with installation of water tanks and plumbing in the toilet and washing machine.

Anyone got any suggestions here? Know any good contractors for this kind of work? Have any ballpark figures for the difference in price for different materials?