I use the thread which matches the quilt. So it may be 100% cotton or blend.
I want my quilts to be used, so I don't care what they look like 100 years later. Let's enjoy them while we are here.
We were celebrating my grandmother's 90th birthday and for dinner I was getting down the good china, my mother said we shouldn't use it, and I said what better reason than reaching the age of 90? And my grandmother said, we always save it for "good". Then she said and there is no one "ggoder" than we are, so let's use it. Have taken that approach to special items every since.
I understand some people use quilts as an art outlet and that is fine, but mine are not, they are to be loved and used.