We could try, I mainly hunt for xp (most fun for me and im making the money lol) but run that mission when my friend is on cause he just remade his person and is trying to get his levels back fast. That one and kill them each and every one of them you can easily get over 1k xp in one fast run. The cooldown is only 5 minutes, ill craft back the ammo I used and run to the nearest place to pick up mail to restock and by the time I do that its ready to go again.
Also we run that cause it doesn't lower your honor. I've never timed it though so we could test it sometime that would be interesting. Kill them each and everyone of them can be ran through in about 7ish minutes (if you run ahead immediately and force the cutscene and don't wait for the dude to ride there). We usually split up and take out all the people fairly fast and 2 sticks of dynamite kill the boss guy and skip last cutscene. Usually nets 1k-1.3k xp (depends if you hit all your headshots or not).