Cor! You learn summat new every day on this site!
The metallurgy, physics, health-arguments, taste effects, cost and fashion of household cooking utensils….
All ignoring one big factor: thermal efficiency.
It will depend on the type of stove but much of the heat from a conventional gas-ring at least, is lost around the sides. I was taught when but a lad never to have the flames protruding beyond the perimeter of the pan.
And years later a former hotel chef gave me the same advice as Lee’s, about not needing costly pans, etc.
As for old pans… I have seen the base of one used as the ashpan on a 2″-scale Sentinel steam-wagon. I would not have known had the owner not told me….
Hmm, there’s a piece of steel plate next to the computer. I’d better get my overalls on and start machining it as intended, and worry about dinner later. Le Creuset from Harrods? Nah – stainless-steel pans from the charity-shop.