It is always cheaper to make them meals at home. But if you travel it is another story. I pestered the management at my work until they bought a mini-oven, the proper one, which I mostly use to warm up or cook my food. I do not like microwave oven, that is. Plus, the benefit is that I can make a sandwich with what I like, and put more into it, like double cheese or my favourite vegetarian pate. It is cheaper, especially long term. If you work 5 days, monday to friday, spend 30 min Sunday doing all the five lunch packs, if you use cook food.
Tell me how it goes.