I thought these were a total gimmick a few years ago when they started coming out, but when my local shop guys recommended them, I picked up a set. Chose this set on amazon for price and reviews.I can't tell water resistance yet, but these appear to seal better than my prior methods of connections. This made a few repairs for me very easily and also perfect for a few tight spaces recently where I would not have had the ability to get both hands and a crimp tool, or definitely not a soldering iron. Especially laying on your back working under a transmission. I don't like hot solder dripping on me.Just using an old heat gun and trying to shrink the ends first to secure the wire first so I can twist the wire back and forth (in a close quarters application) or moving the heat gun on a workbenches project, to gently melt the solder. If all the heat was concentrated on a spot for too long it would probably melt the seal.Let it cool properly before manipulating the wire. It is very flexible.Saved my butt on a few projects already and they work well in an intended application.