As an electrician, I've used similar type connectors for splices. I'm not sure of how good these are, but the ones that I have used, I don't totally trust. There are barbs inside the connector that when shut, push thru the insulation of the wire to the copper wire inside. I have seen these barbs roll to the side of the wire and not make a good contact with the copper wire. I always squeeze the connector with channel locks to make sure. They are quick and you don 't need to cut the wire. This would be the up side.