Twice as fast as the SanDisk Ultra without

For the 64GB microSD card and for comparison for other 4 microSD or SD cards I have following velocity measurements in one USB 3.0 Card Reader (Silverstone) using the test program CrystalDiskMark 3.0:
23 MB / s read, 12MB / s write microSDXC SanDisk Ultra 64GB (bought in October 2012)
12 MB / s read, 6 MB / s SanDisk microSDHC 16GB (bought Nov 2010)
44 MB / s read, 14MB / s write SDXC SanDisk Ultra 30MB / s 64 GB
82 MB / s read, 75MB / s write SDHC SanDisk Extreme 95MB / s 32 GB
18 MB / s read, 18MB / s write SDHC SanDisk Ultra II 15MB / s 16 GB

Compared to a 2 year old SanDisk 16GB microSD card, the SanDisk Ultra is approximately twice as fast in the 64GB variant. Although speed is not at current SD card approach, but for the tiny microSD card that's pretty neat.

Since I had a camera with a memory card Transcend card error and have also read in reviews always problems with various Transcend cards, I entrust to date on SanDisk cards and recommend this in the extended family. In the last 5 years are 10 memory card (microSD, SD, and Compact Flash) in a variety of devices (cameras, camcorders, smart phone) in use and have yet not a single failure.

Hence my recommendation for a hopefully long carefree use and for a pretty good price-performance ratio.