It is described in great detail here: https://www.zdnet.de/88348289...

The QVO is a four-layer storage, which greatly shortens the lifespan. This SSD can also only read and write at 70-100mb/s for larger files, e.g. a Steam library or films. The 500mb/s can only be reached for a short time thanks to the cache. The price/performance of the EVO series is much better.

How big is the copy difference between the EVO and QVO? I have a QVO myself and the 70 - 80MB/s is correct. How is it with the EVO?