I use it when lemon grass is called for and I don't have any.
I find it very clean, un-like lemon balm which I don't care for.
Verbena is great with poultry, veal and seafood. Excellent in ice teas or mashed in a glass with some great vodka I usually chiffinade the leaves as if eaten whole they have kind of a razer edge.
Salad burnet, although I've never grown it personally, I've used it many times and tend to pick the leaves when young and tender as they tend to become bitter as they mature. They have a nice zip to them, almost like peppery cucumber if that makes sense.
Have fun with them and let us know what you end up preparing