There are good old 350's out there.
They don't all fall apart after 15 years.
Just recently Parsonby sold his gunmetal DE zed with a mere 30k miles on it that looked as fresh as they come.
I think the big issues with older zeds would be corrosion (arches, underbody braces and suspension) and smoking engines and gearbox failures.
Sunset orange is very dependent on the ambient lighting.
Under the sun or fluorescent lights I wouldn't choose any other colour as I reckon it stands out like a Candy paint.
Bit on an overcast day it can look like it's just covered in pollen.
If you've seen it in the flesh and really love the colour, have a look at some older ones and hopefully you'll find a gem