Our cars are in the name of whoever picked up the car and did the paperwork - two in my name and one in my spouse's name. I don't see any benefit to going to the trouble to having them in both names. If one of us died, the other would have to do a little more paperwork to sell the car, but that's not really that big of a deal either (I had to do that to sell a couple of estate cars).
Any attorney will probably comment that the legal owner of a vehicle has additional liability over someone not on the title, but the insurance company is the deep pocket on any situation where that comes into play, so I'm not really sure that matters either.