We have the predecessor to PEX... I can;t think of its acronym right now. There have been lawsuits and the makers and builders have had to completely refurbish homes by replacing all the lines with PEX. Our home has the old stuff, and thank god I don;t have any leaks.

I'm a big fan of copper too, like kc2ixe. In a former life, I was a carpenter. Being in the trade for ten years, I learned how to sweat pipes from plumbers. There's nothing like it! Give me a hot water heater to install, and if there's copper to be sweated, I'm there...Mapp gas and solder in hand.

I suppose though, if and when I have to do it, I'll replace out stuff with PEX just because of its flexibility and ease of installation.