Hey guys,
Thanks for all the considered replies. I knew you guys (and gals) would know.
Jen, if you wanna help, I'm happy to hold your handbag while I watch and learn

lol
Simon, I've looked at a corrosion index and it seems the corrosion factor is not something I need to be too worried about.
Rat, (you used to have your name showing - what happened?) - not near the ocean.
Jen, it'll definitely take both - just a matter of deciding on cost and which is better.
Steve and Simon, there wouldn't be a house in WA with copper gutters as far as I've seen. Anyway, today's installers don't offer it. Too expensive anyway!
Marty, I'm heading towards colorbond I think. The Galvanised stuff we have ATM has lasted really well - upwards of 23 years. Much of it is still ok, but I don't want to be doing a part install.
Roger, the only thing historic about it is the owner
Dave221 - I hear what you're saying about the more popular product. I'm thinking that for the extra bucks, maybe there's not that much benefit.
Doppler (Rick) - I agree, my current gutters have been kept pretty clean and have lasted well. But at 20+ years! I've had my money's worth out of them.
Well thanks for all your help guys. I think you've helped me decide on the ever popular, slightly cheaper, colorbond.
All the best gang