I bought this card as I saw it was a bargain price compared to anywhere else. I also saw it had a Class 4 rating. I hoped that given the low data rate my Galaxy S uses even for 720p videos (around 1.5MB/s) it should be fine for using it for videos. After receiving it I found that it is unable to capture at this rate. It can reach around 500MB and then the video will suddenly stop with an error stating card does not support video of this resolution. Never had a problem with my san disk 8GB and could record videos well over 2GB.
Capacity it comes up as 14.89GB, which is a slight bit more than some other 16 micro sd's I've seen. However transferring files can take a very long time. Took nearly 3 hours transferring 6GB from my old SD card to this one, so be prepared for a long wait if you have lots of mp3's and other small files. Large files it's reached around 5 - 6MB/s peak but usually just over 4.5MB/s so essentially reaching that class rating.
In hindsight, I think I'd rather have paid an extra 4 pounds for the class 10 sd card over this.