I thought about using PEX, though wasn't sure if it could take the pressure. A faulty regulator can easily dump 120-200lbs into the system. At least it wouldn't shatter like PVC, though. It's an idea, though I think I already have about half the copper I need for the job. ..though that probably means I'm short 3/4. ;-)
My other house has PEX for its water supply. I have no idea if the house is "normal" but I don't like the stuff. Only one of the outside faucets has any volume and the inside faucets are all weak. It seems there is a lot more pressure/volume lost in the distribution than there is in either the copper systems I've had in the past or the PVC in the new place. One big advantage of PEX for water is temperature stability (someone flushing a john doesn't scald the person taking a shower). Another is the manifold allows one to turn off individual appliances. It's handy for turning off the silcocks in the Winter, though I added ball valves to the distribution system (copper) in my VT house to accomplish pretty much the same thing.