Rebuild K/H Calipers Versus Remanufactured???

I can purchase "remanufactured" Kelsey Hayes calipers for $100-$150 a pair (depending upon the source).

Or... ... ... I can purchase a hone, rubber kits, and 8 new pistons for about the same money, and do it myself.

Who rebuilt those calipers? Did they use "NEW" pistons? Made of aluminum, steel, or made of what?

Which is a better way to go? Why? Thank you FABO community.