Should front springs be replaced in pairs?

Earlier this year my Vauxhall Vectra Estate was found to have a broken front road spring. My local main agent advised me that it was customary for both engineering and safety reasons to replace the springs as pairs. I agreed, as it seemed obvious good practice. However, I was talking to someone associated with engineering who disagreed and suggested that it was not necessary to change both springs. What is your opinion?
Since they are two separate jobs and replacing them at the same time doesn't save you any money, I wouldn't unless you perceived an imbalance after the new spring is fitted. I know it is considered 'best practice' to replace both, but warranty insurers will not pay up for this.
Answered by Honest John on

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