Yes, the faster cards should be better for any application, but I have tested speed class 10 and UHS-1 cards (30 and 45 MB/s) and these cards do not work properly with my unit. The result is data loss/gaps in the recordings which are difficult to detect if you don't expect them. This is probably caused by a software bug. The speed class 4 and 6 cards are fast enough and the recordings are (almost) perfect.
Rickard