Do a few double-blind tests before you guys freak out. I'd be curious to know how many people can actually tell the difference enough to pick the tallow soap based on performance alone. In my experience if you go into this with the belief that tallow-free automatically means worse, then that is exactly the conclusion you'll reach regardless of objective reality. You always tend to find what you’re looking for.
Thank you for being a voice of reason here. If you don't test them blind with several people you already know what the results are gonna be!