Here are the things I like about ACR:
1) It is as fast as the old way I've been using which is tying off in a knot.
2) It equalizes much better.
3) It makes more cord available when anchors are widely spaced.
4) One can better adjust the location of the power point, just by adjusting the length of the loop on the overhand knot.
5) Extension is really minimal. Usually what you have in an anchor is two short arms and one long one. By putting the overhand on the long leg, you've got a limiter knot right where you want it.
6) It doesn't have permanent limiter knots in it like the Equalette that I'd have to untie to use the cord in other applications like the Quad, or lassoing a boulder.
Commenting on the setup that Joseph showed: It is as easy to tie as the ACR, but its disadvantage is that you can't tie a limiter knot in any of the legs. These setups can have one and only one limiter knot, or they won't slide. The fixed power point in Joe's setup is equivalent to a limiter knot.