Quest: piping or fitting which is the problem?

I’ve recently found a house with Quest piping, I beleive the fittings are metal (copper?) and the clamps securing the fittings are also metal. The only place I find plastic are at joints(compression) connecting the addition of a half bath to copper.
My question is: what was wrong with Quest? The pipe or fittings? The current owner has said she has never had a problem, YET some of her neighbors have replaced the piping? Is this a problem? Is this house one that WAS subject to “recall” or replacement? Where can I find out more about this particular situation???