I use them regularly, but I don't know if I'd use them in the first few months. You also have to be VERY careful reading the nut label. I'm always shocked at the amount of sugar in some protein products.
I use them from time to time. However, as already said, be sure to check the nutritional content, especially the sugar and sugar alcohol. Some of the Protein and Energy bars are LOADED with sugar.
As the others said read the labels. I don't eat them very often, but they are my insurance in case I am somewhere that I can't get all of my meals in. I keep a couple in my pick-up for "just in case".