I'm just warning you although the lower capacity cards may have been working for you. When it comes to the 64GB cards many have been failing from the other brands. Only Sandisk has been able to make a very reliable 64GB Micro SD card.

I haven't used Sandisk since my old 1GB cards. My current stable consists of Adata, Transcend, eFilm, Kingston and Topram for SD cards. All have been perfect. When I did pro photog work, I used Topram nearly exclusively (CF) and the only flash card I have ever had trouble with was a single Delkin Devices CF card. Just my $.02. There are lots of card brands I would use. And many are made in the same places any way.
I have been considering a 128GB Lexar for my HiFiMan. http://www.geek.com/articles/chips/how-lexars-flash-products-are-made-20110124/
EDIT: Also, just FYI, you are right about them being integral in the development of the SD standard, along with Toshiba and Matsu****a (Panasonic). It was the non-DRM competitor to Sony's Memory Stick.
EDIT2: Seriously Head-Fi, you are ostensibly a tech blog and you censor the word Matsus h i ta? lol



















