For the record, I still think it’s easier and safer to go with a microSD for your Steam Deck storage needs, and with good Prime Big Deal Days savings on two of the best – the Samsung Pro Plus and the SanDisk Ultra – that opinion remains unbudged. Still, you know what they say: when you’re holding a tiny screwdriver, everything starts to look like a tiny screw. So I understand if the call to replace the Deck’s internal SSD, or indeed that of your Asus ROG Ally, proves too strong.
In which case, have a look at the Crucial P310, which I added to our best SSDs list just last week, and is currently joining in the Prime sale frivolities. Specifically, the 1TB model has been slashed from £128 to £70 on Amazon UK, while it’s the 2TB version that gets a US discount, dropping from $265 to $168.