Memory card and new MacBooks. What’s the “proper” use?

[J.Gallardo]

I’m waiting for a MacBook Pro 16” to arrive home.
I’ve ordered 1TB ssd and it’s enough (by now). But the memory card slot is tempting, as additional storage can be added in a very convenient way
IF the card remains completely inserted
and
IF working permanently with this “mounted disk” is ok for the system and just works.

Of course, cards are nice for porting data from another device, but this is not my principal interest.
I‘m asking if leaving a card always inserted, for data files (and I’m aware of trnsfer speeds) is a “normal” use, or perhaps it’s not recommended, there’re drawbacks, or problems tend to arise.
(My last laptop was a white MacBook. I’ve scarcely used card slot in my iMac, but adding external storage to a desktop is a different thing. This card slot in a laptop deserves to be used, and just the possibility of adding an invisible second slow disk for media data would be a big thing for me).

Um… for media files, what file system would you choose to format the card?

Thank you in advance for your opinions.

 

[bsamcash]

It's actually a common way to expand storage but not a very secure or stable one. SD cards aren't very robust and have a nasty habit of failing after repeated writes.

 

[wilberforce]

The new MBPs have read issues with the SD card slot (see other threads), and SD cards (or other flash drives) are unreliable long term. I have had several failures and/or corrupted files. Failure rate is higher than (spinning) hard drives. They have a limited number of write cycles, so if you do so I would replace it every year or two.