I have been using the card with a Canon ixus 50 and found that for pictures it is fine. For movies, however, about one in three movies that I record stops half way through and the camera displays an E16 error message before turning off. I have wondered whether it was the camera or the card but after reading reviews for this and the 1GB Bytestor card it seems very likely that there are problems with the card.
These problems are not always present and I have been able to record movies for up to about a minute with no problems (I haven't tried to record for any longer than that).
If you only want the card for images then in my personal experience there is no problem with it, but it does seem to struggle with movies.