Never used OS soap. Just looking for soap with scent of old OS.Are you looking for a soap scented like the original OS soap, or a soap that performs like the original soap. That's two completely different questions.
Stirling Spice and B&M are both tallowI am not aware of a tallow based soap with an OS scent; however, you can't go wrong with either Soap Commander Endurance or Stirling Spice, IMO.
I second that choices, very similar scent and it works very well whit Old Spice after shave.I've never used old spice shaving soap but if it smells like the aftershave and cologne then try Stirling's Stirling Spice it's spot on and lathers like a dream.