Polyester or rayon thread?? What's your preference, and what, when, where and why???

I like polyester, rayon fades when you wash it.

I was fossicking through my threads after moving house and sorting the new sewing space. I found spools of rayon that I didn't remember having, but I prefer polyester, and if the quality is good, then it seems the better all-rounder. Just curious what others thought.

The only reason I use Rayon is to clear it out of here. Probably 90% of my embroidery is for children.(My 8 Grands) So the items I make are washed and washed frequently. Often in hot water and bleach. Poly holds up and doesn't fade with that kind of washing. Any kind of clothing or linens I would use poly. If it's not going to be washed or washed infrequently rayon is fine. The new polys are almost as shiny as rayon and come in tons of colors. Hope this helps.

I was told when I started out, if it's going to be washed, used poly as rayon shrinks, but if it isn't going to be washed, rayon as it has a greater sheen, but then the poly's are now made with really good sheen, so just go with polyester. Just wondering what everyone else thinks.