DFCO is not just a Toyota thing, most modern cars have it.

Those who know (the extreme hypermilers who live in places that actually have hills) say that you're better off to stay in gear and use DFCO in most circumstances. The exception would be a really long hill that's steep enough that you can coast in neutral without losing much momentum. If you can coast in neutral for like half a mile without losing much speed, then it is beneficial to do so.

Keep in mind that if you go to neutral, the engine goes back to using fuel to idle, where in a DFCO coast, it uses NO fuel. Unless you want to be one of those people who kills the ignition while neutral-coasting... but that's getting pretty extreme.