The memory card is exFAT formatted and ready to use after inserting. Formatting allows the card in the camera itself only in "low-level" mode, which makes in practice no big difference, you just have to know. Users who use the 550D in conjunction with Magic Lantern to video films, the card must first make bootable with the external tool EOSCard (easy to find on Google), then it works well to load the custom firmware when the camera.
H2testw comes with my card reader at just over 15 MB / s write, so no speed wonder, but enough throughput for video recording.
The long-term field test is still pending, in the short period of use everything looks like a low-budget recommendation.