RE: Case tumbler
In my experience, Midway is the only retailer that charges another shipping charge on an order that has a partial backorder. I really like Midway's fast shipping and customer service, but will not place an order with a partial backorder just for that reason.
I've found some retailers that have very good prices, and better shipping rates too. To name a few, Able Ammo, Mid South Shooting supplies, Grafs, Elk Ridge shooting supplies. Natchez seems to still have good prices, although their shipping rates have increased.
Cabela's shipping rates are extremely overpriced, and their prices are not much better. I avoid them unless I'm buying clearance and discounted items.