Comment by userbinator

What isn't prominently mentioned in the article is that endurance and retention are highly related --- flash cells wear out by becoming leakier with each cycle, and so the more cycles one goes through, the faster it'll lose its charge. The fact that SLC only requires distinguishing between two states instead of 16 for QLC means that the drive will also hold data for (much) longer in SLC mode for the same number of cycles.

In other words, this mod doesn't only mean you get extreme endurance, but retention. This is usually specified by manufacturers as N years after M cycles; early SLC was rated for 10 years after 100K cycles, but this QLC might be 1 year after 900 cycles, or 1 year after 60K cycles in SLC mode; if you don't actually cycle the blocks that much, the retention will be much higher.

I'm not sure if the firmware will still use the stronger ECC that's required for QLC vs. SLC even for SLC mode blocks, but if it does, that will also add to the reliability.