Lexar High-Performance 633x 256GB
Score: 60/100
ADATA Premier 128GB
Score: 75/100Rankings
The ADATA Premier 128 GB microSDXC card delivers solid read performance and rugged durability with a lifetime warranty. Its modest 25 MB/s write speed limits 4K video and high-bitrate tasks. Ideal for budget-conscious users needing reliable Full HD storage on mobile devices.
Lexar's 256 GB 633x microSDXC offers up to 100 MB/s read speed, a V30 rating, and includes a micro-SD to SD adapter for versatile use. Its slower 45 MB/s write speed and lack of waterproofing limit high-end video applications. Suitable for smartphones, tablets and action cameras where large capacity and broad compatibility are priorities.
| Attribute | | |
|---|---|---|
256 GBbest | 128 GB | |
100 MB/sbest | 100 MB/sbest | |
45 MB/sbest | 25 MB/s | |
| ↓ lower better | 453.6 g | 10 gbest |
| ↓ lower better | 1.02 mm | 1 mmbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | | |
|---|---|---|
Storage(1) | ||
Capacity (GB) | 256 GB | 128 GB |
Performance(4) | ||
Write Speed (MB/s) | 45 MB/s | 25 MB/s |
Speed Class | C10 | Class 10 |
UHS Speed Class | U3 | UHS-I |
Video Speed Class | V30 | V10 |
Design(2) | ||
Weight (g) | 453.6 g | 10 g |
Thickness (mm) | 1.02 mm | 1 mm |
General(1) | ||
Compatibility | wide compatibility with any UHS‑I device while remaining backward compatible with Class 10, V10 and U1 standards | Smartphones, tablets, digital cameras, video recorders (includes SD adapter) |
Products in the top-left offer the best value (high score, low price).
Professional testing shows the Lexar 633x card delivers real-world read speeds near 97 MB/s and write speeds around 69 MB/s, surpassing its advertised specifications and confirming its suitability for 4K video capture. Reviewers acknowledge its solid mid-range performance but point out that newer Lexar BLUE models provide higher peak speeds, making the 633x less compelling for users seeking top-tier throughput.
Everyday users praise the large 256 GB capacity, the included SD adapter for easy file transfer, and the peace of mind from the lifetime warranty. They also highlight the card's reliable 4K video performance and compatibility with a wide range of devices. However, some users note the write speed feels modest compared to newer offerings, and the lack of UHS-II support limits its appeal for high-end professional use.
Professional reviewers note that while the ADATA Premier 128GB delivers solid read performance and rugged durability, its modest 25 MB/s write speed and UHS-I interface make it less suitable for 4K video, though it remains a reliable choice for Full HD recording and app storage.
Consumers generally praise the card's reliability, capacity, and broad device compatibility, with no major complaints reported, though awareness of its write-speed limitation varies.
