@Quinquangular the former is better, BCM94352Z isn't as stable on Sierra even till now.
Plus, you won't have handoff working. 2.4G is sometimes flaky in my experience as well.
I just upgraded to 12.6, using BCM94360CS2, working natively with out problem. One thing is you need to get your USB ports fully working(not using the port limit patch) to have stable Bluetooth which means Airdrop/handoff/Apple Watch unlock.
Alternatively you can get PCIe cards like fenvi T919 which is a BCM94360 variant. or other cards like 943602CS and 94360CD, with the exact same adapter to m.2 A/E key or the very rare M Key adapter.