We often use profiled metal as a cladding option in our office. It's a decent cost savings over the alternatives and depending on the house may add to the character.
All non-structural wall cladding types have to meet the minumum NZBC B2 Durability standards of minimum 15 years (or 50 years if structural or braced). Colorsteel warranty their product for a minimum of 15 years assuming it is maintained (washed and installed correctly) and you'll find that most claddings (including timber weatherboards) will only warranty up to this period of time.
As with anything if it's maintained, and installed suitably, it will long outlast a 15 year durability requirement.
I say 'yay'.