their simply cant be that much difference between
the copper and pex for your own home...
so you spend another 800 for the better copper....
2 dollars a foot compaired to 45c.
yes its more expensive but it is your personal home
If you have to save somewhere run the recirc line out
If you are having to cut it that close,
then just put in the pex wirsbo and coat it
with some d-con for the mice..