Not sure of the technical name for them but it is the moulded ones that can reduce the noise at different frequencies by the required decibel level.
By turning up the radio to compensate for the reduction by the moulded earpieces are you not increasing the noise/energy level very close to your eardrum. Seems like you counter the protection you get by increasing the noise level entering your ear !!
Everytime I enter the cockpit after somebody using standard foam or ER25's with or without ANR,I have to turn down the volume settings which are usually very high (almost full in some cases)-----all that noise/energy in your ear no matter what protection you use cannot be good at such close range to your eardrum IMHO
And yes sound clarity in the CEP's is clearer than anything else I have tried while the foam provides good passive protection
regards
PV