WD_BLACK 2TB SN770 M.2 2280 PCIe Gen4 NVMe Gaming SSD up to 5150 MB/s read speed £89.99 delivered @ Amazon

Most enclosures (unless you find a thunderbolt one) are what is now known as USB 3.2 Gen 2×1 (previously USB 3.1 Gen 2) - theoretical bandwidth limit is 10Gb/s (gigabit). In real life, given overheads and converting from bits to bytes, you're looking at an upper practical limit of around 900MB/s - quick search for benchmarks of off-the-shelf portable SSDs suggests performance in the 700-800MB/s range. This all assumes you're using a 10Gb/s capable port - standard USB 3 would be around half that.

Long and short of it is, you won't get anywhere close to what even PCIe 3.0 NVMe drives are capable of in a typical enclosure - thunderbolt enclosures do exist, but are incredibly expensive, and you obviously need thunderbird ports to use them. That's not to say enclosures are worthless - they're still plenty fast enough for a lot of use cases - but a Gen 4 drive is overkill for enclosure use.

Thankyou. Will take a look

If you wait you’ll never build it (as the saying goes). SSDs are at an all time low, some speculation price may increase once supply drops. It’s a good price but you may get it a few pounds less if you wait. Or better, if it’s going to be months could wait and get a fresher drive

Yes it works. Will need to buy a heatsink though (edited)