1. Its called "Stain LESS", not rust free.
2. Stainless is not appreciably different in density then steel, ie same weight
3. SS transmits heat less then steel
4. The suggestion of both would be my choice
5. 409 SS, unless coated would not be my choice
6. Regardless, never "wrap" for the street if you want to keep them.
edit:
"Common Name Density (g/cm3)
Plain carbon steel AISI-SAE 1020 7.86
Stainless steel type 304 7.9"
https://hypertextbook.com/facts/2004/KarenSutherland.shtmlThere are many alloys of each of course, with widely different mechanical properties for each class of material. SS generally has more useful preferred properties as corrosion and higher temps enter the process.