Re: "Get SanDisk Extreme Pro SDXC UHS-II V90 cards."

• Unfortunately, I have to disagree with that recommendation. I've had several issues with SanDisk's build quality lately and they aren't as good as expected for professional use. Technically speaking, the a7 III's write speed is hardware-limited, so paying the premium for V90 cards is basically a waste of money since the camera can't even saturate a V60 bus. I'd suggest these alternatives for a more reliable setup:
• Sony TOUGH-M series SDXC UHS-II V60 because the ribless design is much more durable.
• ProGrade Digital SDXC UHS-II V60 Gold 128GB for better value and consistent performance.
• Kingston Canvas React Plus SDXC UHS-II which performs very well in Sony bodies. Just remember that slot 2 is only UHS-I. If you're writing to both cards at once, the camera throttles everything down to match the slowest card... it's a bit of a bottleneck that makes expensive V90 cards even less useful for this specific body.

Get SanDisk Extreme Pro SDXC UHS-II V90 cards.

I totally agree with the point about not overspending on those super fast cards!! I've been so worried about losing my photos so I actually prefer buying two smaller, cheaper cards instead of one giant expensive one. It feels way safer for my peace of mind and saves so much money! Honestly I'm just so excited about this camera, I took it to a local botanical garden yesterday and the colors were just fantastic. I spent like three hours just chasing butterflies and forgot to even check my storage space lol. My neck is still kind of sore from the strap though, think I need to find a padded one soon. Anyway... but yeah, definitely dont waste cash on speeds you wont actually use.