Rank #9 in Best 256GB USB Flash Drives 2026: 10 Ranked by Their Own Spec Tables
Gigastone Z90 256GB Mini USB Flash Drive
Price and rating as shown on Amazon when we collected them. Both change.
The Gigastone Z90 is a 256GB USB 3.2 Gen 1 drive in a small metal body, ninth in this guide and the dearest of the ten at £49.99. Its listing carries a 4.5 rating from 476 reviews, and the bullets sell it on size, metal construction and compatibility rather than on any measured benchmark.
The number that stands out sits in the specification table, not the headline: a write speed of 100-200 MB/s next to a read speed of 120 MB/s. A drive that writes faster than it reads is not something that happens in normal use, and the listing never explains the gap. Everything on this page — the bullets, the specification fields and the customer reviews — is taken from the Amazon listing. None of it comes from testing we carried out ourselves.
How those 476 ratings break down
An average hides its own shape. This is the spread behind the 4.5 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| Price | £49.99 |
|---|---|
| Rating | 4.5 out of 5, from 476 ratings |
| Stated read speed | 120 MB/s |
| Stated write speed | 100-200 MB/s (as listed) |
| Capacity | 256 GB |
| Interface | USB 3.0, compatible with USB 2.0 and USB 3.1 |
| Item weight | 10 g |
| Warranty | Five years limited warranty from Gigastone |
| Colour field (as listed) | 256GB Z90 USB 3.2 1PK |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchase“yes they do get hot when in use for a long time, but as they are metal they conduct the heat with no problems.I have had plastic thumb drives fail and crack due to heat, but these are robust, and are small so don't stick out of the side of your laptop to get accidentally knocked about.I have used them for a while now, with no data transfer problems, and find the 256 a good size for file storage at reasonable cost.cheaper ones are available but I have had them fail, reliability is worth the cost when backing up filesyes I will buy these again”
Verified purchase“This is a great little memory device. It's a good prices and appears to be robust, compact and reliable.”
What it is up against
The rivals it was ranked against in Best 256GB USB Flash Drives 2026: 10 Ranked by Their Own Spec Tables.
Questions people ask
What speeds does Gigastone quote for the Z90?
The specification table gives a read speed of 120 MB/s and a write speed of 100-200 MB/s. The bullets make no speed claim beyond saying transfers are up to 10x faster than standard USB 2.0 flash drives.
Does the Z90 work with older USB ports?
The listing states a USB 3.0 interface that is compatible with USB 2.0 and USB 3.1, for Windows PCs and Mac computers.
Is the Gigastone Z90 waterproof?
Waterproof appears in the product name, but the specification table lists the product features as lightweight, shockproof and X-ray proof, with no waterproof claim repeated there.
What warranty does the Z90 come with?
The listing states a five year limited warranty from Gigastone.
How big is the 256GB Z90?
The listing describes it as super small, low profile and a mini memory stick, and gives an item weight of 10 g. No dimensions are quoted.
What can I plug the Z90 into?
The compatible devices field lists Windows PC, Mac computer, desktop, laptop, tablet, TV, gaming console and car audio system.
Comments
Reader comments are not checked against the manufacturer's claims above.
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