Conclusion: I am very satisfied! The difference between a 08/15-card as I have in abundance (eg cost of Verbatim's 20-40MB / s class) is clearly noticeable. But I have not carried out measurements and rely on the manufacturer's instructions. , This, however, appear as well as some top reviews write here, to be plausible.
So far, also had no problems in data consistency. The map was now and then packed, then the usual workflow (LR Import), format and on it went.
Therefore: Due to the good price-performance ratio, a strong buy recommendation!