Simpleman96,
All I have used is the Non-FPJ plug, and as well as it is doing I may never shoot the standard FPJ plug. I just love dropping in the bare primer, close the bolt, shoot, open the bolt, turn rifle to the right, primer drops out. It don't get much easier than that. The adapter that holds the primer is inserted in the bolt before inserting into the rifle, it then is held in place and is just an extension of the bolt. You just drop a primer in and close the bolt...the primer pocket is just the right size to allow the front of the 209 to enter freely...then the wider back half is compressed a bit to lock it in...after firing the adapter extracts the primer.
This is the one!
The FPJ plug has a concave that is .300" deep, and the Non-FPJ plug has a .075" high dome. That puts the powder .375" closer to the primer, 1.12" in the standard plug vs 1.495" in the Non-FPJ plug. The standard plug also has a larger .035" flash hole, the Non-FPJ plug has a .027" flash hole. Both plugs have a .125" (1/8") flame channel.
Here they are side by side.