Lexar has always been known for making the best UHS-II memory cards. The Lexar 2000x is still one of the best UHS-II memory cards available to date. Their 633X UHS-I card however, is only just decent. It’s not slow, it’s just not fast compared to what the other memory card titans have to offer.
Lexar cards will become more increasingly difficult to find as they have been discontinued as a brand.
Lexar 633X U3 UHS-I Memory Card Sizes
The Lexar 633X was available in all sizes from 16GB to 512GB. They are no longer available on BHphoto and becoming more difficult to find on Amazon.
I’ve listed all the U3 versions. Be careful as sometimes on Amazon they’ll mix in U1 into the different sizes. This is important because if you’re shooting video on a Sony camera, U1 will not work.
| Memory Card Name | 32GB | 64GB | 128GB | 256GB | 512GB |
| Lexar 633X Memory Card | Amazon | Amazon | Amazon | Amazon | Amazon |
Real World Memory Card Performance
Compared to other brands and their performance the Lexar 633X sits about where the Sandisk Extreme Plus is in terms of both read and write speeds and in-camera performance. This makes the 633X a great all around card that’s not too expensive.
There is also a U1 version of this card that I have yet to test.
| Memory Card Name | USB 3.0 Read | USB 3.0 Write |
| Lexar 633X SD Memory Card | 93.3 MB/s | 67.3 MB/s |
Compatibility
Speed Class: Class 10 / U3
UHS-I devices
Reliability
Limited Lifetime Warranty