Ive tried searching but PDN is too short for the search engine. Anyways, which one will yeild a higher compression? Of all the threads I can find, I can only find dome height and compression height(PDN has a 1mm shorter dome but .5mm higher compression height than the PM7/P29s). Ive tried working backwards with the D-series calculators and got 4.7cc as the dome volume for the PDN. Is this right?