In Reverse Order...........
monkeyboy
Yes. The Old, Original Lee Autoprimer seems to have been the best. All other just don't match up.
justsomeguy
From what I can tell, just about all mfgrs hand primer shellholders are not interchangeable with other shellholders. They don't even work as shellholders in the reloading press, except RCBS.
Mikee Loxxer
Well, after your post, I checked out the Forster Co-ax Primer Seater. Had never heard of it. No shellholders to interchange. Cool. But....you gotta be a Registered Professional Engineer to set it up and run it. [I am, but still intimidating, like you said.]
OOBuck
My RCBS hand primer has a non-captive pushrod. Just drop it into the hole. Unfortunately, turn the primer device past horizontal, the pushrod drops out to the floor Yes--of course--don't turn it upside down. Well, that's beyond human nature. Hence the hands-and-knees search.
Summary:
Still searching for the Golden Hand Primer.
sfg