I have noticed that there is quite a difference between Sandisk MicroSD and Transcend branded ones. These are the standard range of MicroSD made by both brands. 1)Firstly, Sandisks adaptors are made in China and the microSD is made in Taiwan, whereas Transcends are apparentely 100% made in Taiwan. 2)Transcends hold (when formatted in default FAT) 952mb , whilst Sandisks hold 968mb as reported 3)Transcends write and erase slightly slower than Sandisks. I timed a 60.8mb movie on my phone. The Transcend completed the write in 21.01s. The Sandisk completed it in 13.08s. 4)When being used, and data is read, there are very, very slightly higher load times with the Transcend, but these are fractions of a second compared to the Sandisk. Un-noticable when running software. 5)Transcends have a lifetime warranty. Sandisks have a 5 year limited warranty. 6)Transcends have no special features, whilst Sandisk quotes itself as having "Built-in security features enable users to download, store, and play secure content" 7)Yet the Transcends are 2/3 of the price of the Sandisk at retail, so this is perhaps not a bad deal. My question is, why are there capacity differences between the two cards , and why the speed differences?  Does the faster card (sandisk) use better quality components?  What are the security features the sandisk introduces , and are they ever needed?