First off, I've always bought Sandisk for the warranty under the reasoning that a lifetime warranty means they must be a little better than the others and Sandisk's lesser lines. I have 5 Class 6 SD 8GB Extreme III series cards all pushing 5 years old now with zero problems, all of which write nearly twice as fast. Not sure what the limitation is, Class 10 UHS-1, and 5 year newer tech should blow these away.  The 'micro' packaging shouldn't make a difference either.  I can only guess it's marketing differentiation.Again this card will write at published specs but you may want to check out the Sony SR32UYA/TQMN of the same capacity, it reads and writes faster and is a similar price, though only a one year warranty. I picked it up with a Hisense 7 Pro tablet (awesome) and couldn't wait, and they were on sale locally for $26. Was a pleasant surprise. Came with a SD adapter as well and some file recovery software (a link).  Not a fan of Sony web sites support or or documentation for any of their gear the last 15 years but these are commodities now I suppose and you can't expect much any longer. I now kind of think if these things work 30 days, they'll probably work 5-10 years until they are obsolete. FYI:The Sandisk and Sony are both made in China.