We had one flying around the potato field, yesterday.
Poor thing was carrying a cicada and looking for her burrow, which we had just (apparently) destroyed in the process of digging up our potatoes.
She flew around with that huge bug in her arms for at least 5 minutes - I couldn't believe she could even maintain altitude with that payload.
They are about the least aggressive wasp you could ever hope to encounter. They will buzz us if we are near one of their burrows, but they never get really close.
Around here they are considered "friendlies" and enjoy life in the no kill zone.