Many things play a role in a rods sensitivity.. modulus is just one. Rod design (how the actual rod is built, guide alignment, spacing, thread, finish, guides) are just a few.
Blank companies don't tell you exactly how they build the blank, modulus is more of a consumer "idea" than a manufacture "idea" just like IM6 vs IM7. Which one is better? Hold up a Berkley "Buzz" IM7 and then hold a Rainshadow. Now which one is better? It's about personal preference, and feel, warranty, cost, QUALITY, etc.
I hope this helps..???