Does anyone use these types of foil tart/pot pie liners for steam or dry baking?

"…heavier looking foil pot-pie/tart pans…"

Yes. I use Hefty EZ Foil Cake Pans –

The larger smooth bottom, without all the folding of the sides, works well for forming.

I cut off the rim then shape them around a form, usually a roll of duct tape that has been reduced in diameter to create the perfect fit in the pan of choice.

If you want to be real clever, form an "over fitting" lid first, then strip off enough duct tape to create a slightly small "pan".

The duct tape idea is downright genius. I think those cake pans are easy to find in store too. Thanks.