
SanDisk Extreme 256GB
Score: 87/100
ProGrade Digital Iridium 256GB
Score: 47/100Rankings

The SanDisk 256GB Extreme PRO UHS-I card offers high read/write performance and rugged durability, making it suitable for 4K video and burst photography. Its lifetime warranty and RescuePRO software add value, though the UHS-I interface caps ultimate speed potential.

The ProGrade Digital Iridium 256 GB UHS-II V90 SDXC card delivers ultra-fast read/write performance and rugged durability, making it ideal for high-bitrate 4K/6K video and RAW burst photography.
| Attribute | ![]() | ![]() |
|---|---|---|
256 GBbest | 256 GBbest | |
200 MB/s | 300 MB/sbest | |
140 MB/s | 275 MB/sbest | |
— | 3 yearsbest | |
| ↓ lower better | 13.6 gbest | 15.9 g |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Performance(5) | ||
Video Speed Class | V30 | V90 |
Maximum Read Speed (MB/s) | 200 MB/s | 300 MB/s |
Maximum Write Speed (MB/s) | 140 MB/s | 275 MB/s |
Bus Interface | UHS-I | UHS-II |
Speed Class | C10 | Class 10 |
Warranty(1) | ||
Warranty Period (years) | lifetime years | 3 years |
Physical(1) | ||
Weight (g) | 13.6 g | 15.9 g |


Products in the top-left offer the best value (high score, low price).

Professional reviewers praise the card for delivering reliable 4K video capture and exceptional durability, but caution that the UHS-I interface limits its top-end performance compared to UHS-II cards.
Everyday users rate the card highly for reliability, capacity, and ruggedness, noting flawless 4K recording and survival in harsh conditions, while some complain about slower-than-advertised transfer speeds and occasional older-model shipments.

Professional reviewers from B&H, Leica Camera USA and Filmtools commend the Iridium 256 GB card for its rock-solid reliability, V90 certification and error-correction, highlighting its suitability for high-end DSLR, mirrorless and cinema cameras.
Everyday users consistently rate the card five stars, praising flawless 4K recording, lack of dropped frames and the usefulness of Refresh Pro™.
“Perfect for my Panasonic Lumix GH5-records 4K video without hiccups.”

“Used it for a month-long safari-survived dust, heat, and rain. No data loss.”

“Advertised 200 MB/s, but my MacBook Pro only reads at 70 MB/s.”

