I have used well over a thousand of these on numerous layouts of the past 28 years with out a single failure. The ones used on the layout 28 years ago are still there and providing electricity where needed. Some of these are installed in moist basement in NC and no failures in 15 years, including the layout having water run over it in one storm.
They are like anything else, just make sure you use them correctly.
Also, in looking at the Wago connectors that John H shows above, I do not see any that will tap into the buss wire without cutting the wire and then splicing them back together. It seems to me that every time you cut the buss, you are introducing another potential failure point.
Happy railroading,
Don
