Which Headset?
Rich,
The difference in microphones is implementation specific. The dynamic microphone uses a vibrating membrane as one plate of a capacitor to create a transducer to produce the signal for input to the pre amp. In simple terms an electret mic still uses a pre amp but uses the characteristics of the material ( inbuilt charge) to vary the signal when the material is vibrated.
In terms of which to use..I don't think it really matters and will not intrisically affect compatibility. What will affect compatibility is the impedance of the headset. I don't know about the 8003 but I use an 8006 which is adjustable from inside the earpiece so that you can set it to work with different headsets.
I have only ever experienced this problem in one particular aircraft across several types I have been using a Peltor 8006 for a few years now.
There is a thread on here about the adjustment , have a search for Peltor 8006 , it contains pictures and instructions on how to adjust the headset.
cheers,
Squawk