I like one border. Mostly because I finish the quilt top, cut the border (usually around 6"), get bored and move onto a new quilt top. So the border sits next to the quilt for a good few weeks before I finally attach it. And if it takes me that long to attach one border, I know I won't get 2+ done very quickly :)
I did one with 3 borders, and I really liked how it looked, but it's just too much focus for me :mrgreen: