When I went to France last year I came fully armed with two Leica M cameras with a couple of lenses each, an X-Pro, a LX-5, and a Rolleiflex. I ended up using the Rolleiflex the most, with the X-Pro a close second. The Leicas were more or less unused.
I found the Rollei's square format to be good in alleys and narrow places, and I simply enjoyed using it. The X-Pro was used at night, amd for snap shots, my girlfriend used it for the most part.
I am going on vacation tonight, and I have brought a Nikon SP, a Leica M4M, the X-Pro with it's recently acquired 14mm lens, and the Rolleiflex. I will be shooting mostly slide film this time around, the southwest of America is colorful. I will do a bit of B&W shoothing in the ghost towns (what is left of them) and such.