Remington does not approve the use of BH209. However, if you want to shoot BH in an RUM, then you need the Arrowhead replacement breech plug. Yes, its worth it.Trying to decide between a cva paramount or the Remington ultimate. Wondering if the ultimate has a fast enough twist to support the new powerbelt 325 elr? Also does Remington allow the usage of blackhorn 209?