I have used plastic LOckitt connectors, which seem to be a new version that combines the Scotchlock and wire nut concepts.
Scotchlock connections are not very reliable, they seem to pull apart easily unless they are installed in perfert conditions. I rarely encounter anything but undercounter, not wire slack and other problems in my RV. So I won't use scotchlocks again.
Lockitt connects are expensive, as they may be on patent and have a small distribtion. But the job does get done without the stress of the alternative.
Wire nuts only for AC. Use a more reliable method for stranded DC wire.
