Dos, I'm not familiar with the term primer hold down die, can you explain?
As for the neck sizing die, my only experience is with a lee. It seems to work good for my Savage in 223
On some of the higher station presses there is extra room. On the station that primes from below you can put a die on top that holds down the case so your priming is more consistent on less flex on the shell plate. This is for a mark 7 evolution. And I see a mighty armory die but not sure if it even works with 223.
One thing I used to do on my LoadMaster was use the sizing die in station 2 (I think) with the decapping pin removed. That way I was sizing and priming at the same time so the case was held firm. I used a universal decapping die in station 1 to deprime. Could you do something similar with your press?