I have not tried any Rainier bullets yet (I load/shoot Berry's DS in 9X19) for the .451 calibers (GAP, ACP) but may add some on the next big order I do.
I've had really good success with Hornady 185 gr. XTP, which I originally got free when I bought one of their presses and some dies. They are very good through all of my GAP and ACP pistols, and I'm always open to trying something different if others have some good feedback.
I've got a list with some Precision Delta and Montana Gold bullets on it, and I'll be putting in an order for some Rainier to see how they run through my guns.
Thank you for the feedback, guys!
Shooter of many Glocks
Ammo by Dillon and Hornady