I usually use SanDisk, but I hear good things about SamSung Micro SDs too IIRC.
WHat is the difference between the different versions of Micro Sd for example SanDisk Ultra and Extreme? Which is the fastest, and most reliable for flashcarts? I'm thinking about expanding to a larger size Micro SD for my SD2SNES, and the upcoming Mega SD, and I want most reliable I can get. I'm thinking of at least going with 128 gb versions.