I have so far on my EOS 550D always used a SanDisk 8GB 30MB / s. 5 RAW photos in a row were no problem at all. Then you had to wait until the photos on the card are. This (45MB / s) Edition is 7 RAW images in a row. Although a difference, but I would have expected more. Nevertheless, it must be said that SanDisk is one of the best brands of memory cards. Until now had never experienced any problems.
Strong buy recommendation. Otherwise, I can use the 30MB / s Edition also recommend.