Making your own lunch has its advantages: you can eat what you want, and you can eat healthy. Typically the cheaper option as well. However, the variety is crap once you reach the week's end, and face it, it's boring.
I love eating out, but with only a half hour's time, it becomes very difficult to eat well. Most healthy places aren't necessarily fast. It can get expensive, so find a place near your office that is your go-to: cheap, semi-healthy, but delicious. I'm wishing you good luck with that one.