I have a dedicated meat-hauling frame, the Kelty Cache hauler. Packs weight much (MUCH!) better than my kifaru duplex or bikini frames do. Enables me to have a dedicated meat hauler. Also use it for ruck training prior to elk hunting season. Don't have to fart around with removing bags, adjusting clips, or any of that stuff once I'm in meat-packing mode. It also costs about $125-$150 (or $350 cheaper than what you are considering).
What I take with on most of my hunts:
1. Frame and larger backpack for overnight hunts
2. Frame and smaller backpack for day hunts
3. Meat-hauling frame pack
Setup #1 is the primary go-to for most hunts. Setup #2 is the backup to #1 and is used when I'm day-hunting (going into a new area I don't know, hunting a limited-quota/draw unit with fewer hunters, hunting an arid state with NO water within a reasonable distance, hunting an area with roads all over the place). Setup #3 is only used prior to the hunt for for training and then for packing out meat when I kill something.