For real emergencies you will want something that removes energy completely, not only from the router but from the Shapeoko also.
For less severe “wait a second…” situations, and for the ability to just pause and later resume where you left, you may want to utilize the “feedhold” signal of the shapeoko controller, and connect it to a momentary push button on your control box. We have a thread here that covers that.
My control box is very, very rudimentary, but I have found it to match my need perfectly over the years
