Stuart
I replaced the water lines in my '73 with PEX and love it.
We have went to the mountains twice during the winter months and have had no
problems with the PEX.
I did not use the crimp style fittings, because I figured if I ever did have
problems with a fitting leaking I could just R2 fitting instead of having to
cut and splice etc...
Also, I priced the PEX at the Home Depot here, but bought mine from a plumbing
supply shop for about a third of the HD price.
Bobby