omg---
i've been quilting with poly thread for years.
it is beautiful-
lots of thread companies carry wonderful poly quilting threads-
don't be narrow minded- you miss out on so much when you are not willing to try new things- if it wasn't ok to use- there would not be this HUGE market---
quilters quilt with lots of different threads- poly, rayon, nylon, wool, metallics, silk....and even cotton threads....make beautiful quilts that stand the test of time