Started by former SanDisk and Lexar executives, ProGrade Digital is a relatively new and promising company, so halo products like this are interesting on several levels (and not just from a marketing perspective). The key takeaway here is the extremely high sustained write speed of 2,800MB/s, which is crucial to know when looking to buy for 8/4K and high-frame-rate (slow-mo) video. However, that all-important key message has been fudged by saying “up to 2800MB/s.” Surely a sustained write speed is a minimum, not a maximum implied by the “up to.” Makes no sense from a marketing perspective. A high sustained write speed is not really important for stills photography, even…