Not sure what's up here, but when I set the config option to true, the recipes still use only Iron instead of Steel, even though I have Mekanism and Tinkers' Steelworks loaded, which both add Steel ingots. Even setting the config on both client and server does nothing.

Running Forge 1207
BR 0.4.0rc3
CofHCore B3-26
CofHLib B3-20
Mekanism (+ Tools & Generators) 7.0.0.75
NEI 1.0.2.28
TConstruct 1.6.0d39
TSteelworks 1.0.2

This is probably another oredict problem. I'll take a look.