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"High endurance" MicroSD cards -- Worth the cost?

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Sandisk (and others) market their high endurance memory cards as being temperature-proof, waterproof, shockproof and x-ray-proof (which I believe they all are anyway) and guarantee write enduring in hours of recording time (which is a little meaningless in terms of digital video).

There doesn't seem to be any technical details with respect to these cards. Would they just include more memory for wear-leveling, use a different type of NAND or is it just marketing BS for plain old SD cards?

Sidenote: from what I've read 'write endurance' is often not too much of a problem, but 'bitrot' (shelf life) can cause you problems after only a few years.

Do they provide specs for the flash data-retention life?  Eg 10 years? 

Yep bitrot is more of a problem since the write endurance tends to be handled by the controller chip remapping pages as they get written too much (unless you really write all the time).

What you probably get in the better cards is the more reliable less crowded flash technology.

They put varying amount of data in flash cells:
1 level: SLC flash
2 level: MLC flash
3 level: TLC flash
4 level: QLC flash

More analog levels you use inside a cell the sooner the cell might leak some charge and change state. So SLC is most reliable where the cell is just a binary 1 or 0. Most flash storage right now uses TLC, but most of the new high capacity flash is QLC. If you buy a fancier more expensive SSD (Such as the Samsung 8xx 9xx PRO) then you get MLC flash in it. Getting SLC flash in a SSD is pretty hard unless you buy some specialized enterprise SSDs that cost an arm and a leg.

So if you can get a memory card with MLC flash in it that will help reliability as opposed to the QLC garbage they are now rolling out everywhere for consumer stuff.

I can understand that multi-levelling (more bits per cell) reduces your "noise" (bitrot) tolerance, but what about other factors? 

Surely all of the other fab parameters (cell size, material, quality) would have just as much (or even more) impact on things like cell charge  leakage rate?  From what I've read there is also ECC going on to try and correct these problems, something that I suspect everyone will implement to different degrees.

ie is there any data to suggest that SLC/MLC/*LC is the most important thing affecting shelf life for flash?

I probably should elaborate, I intend on using these cards in my car's "dashcam". It won't be recording all the time, only when driven. Some 2-3 hours per day.


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