Just my opinion.
I am a nurse and usually people sleep best with natural fibers. Polyester does not "breath" as well as natural fibers. Waking up during the night too hot or sweaty may possibly be fixed by changing bed linens to natural fibers.
That being said, if the quilt is for back of the sofa or wall hanging then poly is fine, but if the quilt is for sleeping under then I would recommend cotton.