Ervin Photography did my senior pictures back when I was in High School (ages ago, I know).
I must say, the pictures turned out fabulous. The color and clarity was sharper than anything we ever took with our own camera.
But I must say, they were pretty expensive too. We wound up buying the "minimal" package... a few 5x7's for grandma, etc, then took our own photographs for wallet sizes to give to friends.