I also do notice a difference in both low and high range frequencies between my Sennheiser and Earpods on listening tests. But still the Earpods are very very good and have to be some of the best value for money on the planet?
I would say that all 3 headphones would benefit from a Headphone Amplifier.
Also note that the SPL measurement is made at one frequency only. Generally seems to be 1KHz. So the sensitivity may seriously degrade at the ends of the claimed bandwidth.
It is interesting to note the technical differences between the sets as optimized for different applications.
Given the complexity of comparing headphones due to many parameters way beyond this list I would think that the 'crowd sourcing' method of opinions may be the best way to make a determination as to which headset is best for you.
Headset technical comparison