Sam,
If your polybutylene pipe is assembled with copper crimp rings and
copper or brass fittings, you should have no problems. The poly tubing
was not ever the problem. The problem occured when it was assembled
with aluminum crimp rings and/or acetyl (grey plastic) fittings. So
check your installation. If there are no aluminum crimp rings and no
plastic crimp fittings, you have nothing to worry about.

Stretch