What do you use?
Whatever works for you!
That goes for the actual quilting as well as the piecing.
Some will tell you to never use polyester on a quilt. Others only cotton.
While others say, Whatever works for you!
Some have thread stashes offering them lots of choices!
@Julienm1 ... There's no hard and fast must-do only-do absolutely-do rules!
You. Do You!