Has anybody used these and are they fairly simple to wire up? Do they come with instructions like Atlas signals?
Yes, I've used a lot of them. No, they are not "plug-n-play" like the Atlas signals. NJ International signals just have wires coming out the bottom that have to be connected to a controller. You receive basic instructions showing the color coding of the wires and recommended resistor values for various power supply voltages, but that's all. The rest is up to you to figure out.