I guess that is geek lingo, so I would prefer to call it "two friends both out and about taking pictures at the same time".
Me with Nikon D3s(called Bob from here on out) and Aleksander With with Leica M9p(he named her Aisha).
We called it a stand off on Twitter.
It depends on your preference.
Bob is big and heavy and Aisha is more handy.
Also it depends on the lens!
If I am not mistaken Aisha had The Leica Summicron
50 mm f/2 and Bob had a 85 mm f/1.4
(I realize that I should have made a note of this...)
If I am lucky I can show some of the pics that Aleksander took later - I have to ask him nicely;)
I really loved the D3s, I have to admit.
But for a relative small girl like myself (my muscles are hidden...)it takes a physical tole to carry around "Big boy Bob" all day.
I think I would prefer Bod in the studio and Aisha (or Kurt) in the streets.
Take that with a pinch of salt will you, since I haven´t tried either cameras in studio...
Anyways here is a selection of my outcome.