Samsung 870 QVO 4 TB SATA 2.5 Inch Internal Solid State Drive (SSD) (MZ-77Q4T0) - £174.61 / £124.61 After Cashback @ Amazon

The EVO is the better SSD.

EVO uses 3-bit TLC and the QVO using 4-bit QLC.

I'm still drunk, apologies

Putting all your data into one single drive means that if the drive fails, all your data will go with it. Spreading it across multiple drives will technically improve your chances of not losing all your data at once (increases your chances of losing partial data). So you should make copies of your data on another set of drives... Well, that's called backing up. If you have your data backed-up, it doesn't matter if you put all your data onto a single drive, depending on the criticality of your use case of course.

These days SSDs are very reliable especially from known brands such as Samsung, Crucial, and Western Digital, and they're cheaper than ever before so there is no excuse not to have back ups either.

Bottom line is, if your data is crucial (heh) to you or your time is important, always back it up, doesn't matter whether they're on 1 or 5 drives. If your data is not important to you, back it up anyway. If you're on a budget and can't afford extra drives and your data is not important to you, then do whatever you want, I guess.

For long-term storage I'd still prefer a spinning hard drive, both for cost and longevity. That doesn't mean an SSD doesn't last long, it just means a hard drive would last longer. I am perfectly happy storing all my data on a 4TB SSD, as long as I have it backed up. You could've just ignored all this long rambling of mine and refer to your own comment instead: always back up regardless of medium. (edited)

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