On our remodel I told our builder I wanted copper on all drinking water sources. I rationalized that I spend enough time in places where I can't drink the water and I wasn't doing that in my own house.

We are using PEX for the baseboard heat, PVC for waste lines, and copper for all supply. I know that PEX has its benefits but it hasn't been around long enough that I'm drinking from it (even though I drank from a green garden hose as a kid, I know it's somewhat irrational but it's my money).

I don't think your choice will affect resale UNLESS someone finds out that it does leach chemicals and then it will be like Chinese drywall and lead paint - a big deal for some people but not all.

we went with PEX because our well water will not work with copper piping, unfortunately. i hope chemicals don't leach from PEX piping!

PEX was invented in the 1950s and has been used extensively and very successfully since the 1970s....in Europe! I think the big question over its use for potable water here arises from the effects of the high chlorine content in our water. In most of Europe's potable water chlorine is almost non existent. Perhaps the amount of chlorine we are drinking should be our larger concern!