Every site I have looked at, including Sony says the upper micro sd card limit is 128 gb. As I posted just above, the real test of the 200 gb card will be when using it with more than 128 gb of music stored on it. I think it is fantastic if it works and I'd assume Sony would be revising their advertising materials accordingly. I seriously doubt I'll exceed a total of 256 gb myself but it would be nice to know I could! I'd also point out that you can buy two 128 gb cards for approximately $160 and the 200 gb card is $250. I think it is worth the convenience to have everything on one card but others may think differently.