The robber flies represent one of my favourite fly families, Asilidae. I like Asilids mostly because they are such awesome hunters. They perch on the edge of a leaf or other exposed area, and dart back and forth, snapping up prey. Also, the family contains some impressively excellent bee mimics.
But I finally caught some photos of these guys (alas, too late for my Fly day post).
PS. I defended my doctoral dissertation today…I am a doctor! You can call me Dr. Standingoutinmyfield. Or just Standing is fine too. 😉