You don't want a vest that just meets a flame resistant standard because that's not proper for ANSI 107. You want to make sure you have a high vis 107 vest and an arc flash vest that meets ASTM F1506.
It might have mesh in it, which makes it much more comfortable, but this mesh vest is only about four calories of protection. If I need eight calories, I'm wearing the eight calories in my shirt. To have the four calorie vest over top of the eight calorie doesn't decrease it and make the eight calorie shirt a four. It actually means I probably have some more protection where the vest is.
Make sure that you wear an arc-rated vest if you're exposed to electric arc.