While all SSDs are going to be faster than physical, spinning disk media, the experience between different SSDs and the flash they have within varies quite considerably. Flash storage most commonly uses what’s called NAND to store data, and within, there are varying types of NAND, all of which have different speeds and efficiencies. QLC, or Quad-Level Cell NAND, is known for being the cheapest type of NAND available in consumer SSDs, and because of its all-around poor performance, it’s time we left it behind for good.