KSY
I tested it in several UHS-1 compliant devices and found the write speed at 11-12 MByte/Second. Sounds fine for a class 10 card but this is not what I was paying for. I don't expect it to run anywhere close to UHS-1 interface speed (104 MB/S) but it should be close to 30 MB/S as the manufacturer advertised. I have a lot more choices if I am only looking for a class 10 card.Indeed, microSD cards are usually slower than full-size SD card. They use the same Flash controller so the reason is really microSD cards use slower NAND Flash. Manufacturers know you are not going to use microSD cards in high-speed SLRs so they get to sell you lower quality NAND at a premium. My advice to you the photography enthusiasts is to buy full-size SD cards rather than microSD cards with adaptors.That said, the compatibility is great. It works great with my tablets, PCs, GPSs and phones. That is what I like about SanDisk. They do thorough compatibility tests before product release.