I've been using them for the low current apps.(ballasts), and for capping off wires.
I'm still skeptical about anything that just bites on a conductor in just one spot.
Given some time, although their track record so far seems to be OK, there is no contact from one conductor to the other, besides the flimsy metal inside the "whacko".
I know I'm an old f**t, but I still think they're junk. [Linked Image]