My first card...
ProGrade Digital 240GB CFexpress 4.0 Type B Gold Memory Card
BH # PR240CF4MC MFR # PGCFX240GBTBH
1 Review
Key Features
240GB Storage Capacity
Max Read Speed: 3100 MB/s
Max Write Speed: 1600 MB/s
Min Sustained Write Speed: 700 MB/s
Records Raw 8K, 6K, and 4K Video
What I bought with my 2nd Z8...
Video recording gets interrupted due to insufficient sustained write speed (not listed).
SanDisk 128GB Extreme PRO CFexpress Type B Memory Card
BH # SACFEP128GB MFR # SDCFE-128G-ANCNN
1,357 Reviews
Key Features
128GB Storage Capacity
Max Read Speed: 1700 MB/s
Max Write Speed: 1200 MB/s
Records Raw 4K Video
Compatible with Select XQD Devices
Downloadable Photo Recovery Software
What I'm considering buying when I can save enough...
If I understand correctly this card has a high enough sustained write speed for most anything the Z8 requires. I'm not sure so I'm asking.

(i.e. the fool really doesn't know).
Delkin Devices 512GB POWER 4.0 CFexpress Type B Memory Card
BH # DEDCFX4P512 MFR # DCFX4P512
52 Reviews
Key Features
512GB Storage Capacity
PCIe 4.0 x2 Bus
Max Read Speed: 3650 MB/s
Max Write Speed: 3240 MB/s
Sustained Write Speed: 820 MB/s
Records 8K, 6K, and 4K Video
Records High Bit Rates and Frame Rates
Records Raw Photos and Rapid Bursts
Resists Shock and Water
I notice in photos the ProGrade CFexpress B cards has aluminum that wraps around from the back into the channel where the locking notch is. I wonder if that aluminum wasn't pressed tight in place and caught on the card slot and would not allow full removal from the card slot.
Dave