SanDisk Ultra Dual Drive 256GB USB-C Black
Score: 71/100
Zarmst USB-C 4-in-1 Flash Drive 256GB Blue
Score: 69/100Rankings
The SanDisk Ultra Dual Drive 256 GB combines USB-A and USB-C connectors in a retractable design, delivering up to 150 MB/s read speeds and a 5-year warranty. It lacks waterproofing, hardware encryption, and detailed write-speed specifications, which may limit its appeal for power users. Best suited for mobile users who need quick cross-platform file transfers and a compact, high-capacity drive.
The ZARMST 256 GB 4-in-1 flash drive offers a versatile multi-connector design and an encryption app, making cross-platform storage convenient. However, its real-world transfer speeds fall short of claims and it can become hot during use. Best suited for users needing occasional backups across devices.
| Attribute | | |
|---|---|---|
256 GBbest | 256 GBbest | |
150 MB/sbest | 80 MB/s | |
— | 30 MB/sbest | |
| ↓ lower better | 9.1 gbest | 32 g |
5 yearsbest | — |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | | |
|---|---|---|
Performance(1) | ||
Read Speed (MB/s) | 150 MB/s | 80 MB/s |
Connectivity(2) | ||
USB Version | USB 3.1 Gen 1 | USB 3.0 |
Interface | USB | Lightning, Micro USB, USB-C, USB-A |
General(1) | ||
OS Compatibility | Android, iOS | iPhone, iPad, Android (OTG), PC, Mac |
Build & Design(2) | ||
Weight (g) | 9.1 g | 32 g |
Dimensions (L×W×H) (mm) | 38.1x20.7x9.4 mm | 42.93×22.10×5.08 mm mm |
Features(1) | ||
Hardware Encryption | false | true |
Products in the top-left offer the best value (high score, low price).
Professional reviewers highlight the high read-speed performance and the convenience of dual connectors, but note the lack of detailed write-speed information and limited durability features in the base model.
Everyday users appreciate the convenience of quickly offloading phone media and the portable design, while some express disappointment with slower real-world speeds and wish for better ruggedness or security features.
Professional reviewers commend the ZARMST drive for its versatile 4-in-1 connector layout, compact thumb-drive form factor, and the security-focused app that adds encryption and fingerprint unlocking. However, they criticize the gap between advertised and real-world speeds, heat generation during transfers, case-related compatibility issues, and raise doubts about the true usable capacity and overall build durability.
Everyday users love the convenience of a single drive that works across iPhone, Android and computers, especially the one-click backup app and the ability to move large media files via USB 3.0. Recurring complaints focus on slower-than-expected transfer speeds, the device heating up, incompatibility with phones in cases, and uncertainty about whether the full 256 GB is actually usable.
