So... I own the original now-discontinued Sir Irisch Moos shave soap as well as the still-available Sir Irisch Moos fragrance. In its original form, the fragrance has a little more detail and freshness compared to the soap.
I Rich Moose shave soap does a nearly perfect impression of Sir Irisch Moos Eau de Toilette in all its brilliant spicy-aromatic-green glory... Comparing the two side by side, I'd say Stirling's soap base lets far more of that fragrant detail through than the original product's soap base did. The Stirling version might be stronger than the original soap, too. If you're looking for the SIM shave experience but can't afford black market prices for one of the original shave sticks, go with I Rich Moose. It'll scratch the itch!