This is something we have been worried about as well. Still not convinced the SLC cards are worth it as there are many other factors affecting performance/durability. There have been a few other developments in this space which are good to be aware of:
- A lot of the ‘industrial’ part of the industrial cards is about having wider environmental ranges rather than increased write durability and the designation doesnt generally mean they are better in this regard. Industrial SD cards are often also targeted at specific applications and its worth contacting the distributors to find out what they are usually used for (i.e. they may not be suitable for use as RPI system/boot disk).
- There are consumer cards with wear levelling now like WD Purple. These may offer most of benefits of industrial SLC at much lower price points.
- Manufacturers have ranges of ‘endurance’ cards aimed at video dash cams. What exactly is meant by ‘endurance’ is unclear and it appears to be largely a marketing term. But it is worth noting they are warrantied for either more years of use and/or higher amounts of write. Some may also have other features like wear levelling to help them achieve this (but there are other strategies manufacturers cam employ to increase durability).
- There is a newer intermediate class of memory called pSLC which is cheaper than SLC but has better write durability than MLC. I dont think this has found its way to consumer cards as of yet but it is offered as part of industrial SD card ranges.