Hi,
This is a true case of one market segment impinging on another.
For years,there has been a market push for faster SD cards with higher capacities for cameras or phones, for example.
Many microSD/TF card users do not need even 8 Gb of storage (single board computers, firmware upgrades) and these devices sometimes cannot support the faster, higher density card.
In general, most cards never get used to high capacity or reach R/W failure. As such, I generally purchase 8/16 Gb cards at the low end of the price range and always keep 8 to 10 new ones in a drawer for immediate use.
(Some Chinese sources are now providing Terabyte cards¡)
Larry
AC9OX
Larry McElhiney