Hi ppl, I'm hoping to buy a Panasonic SD90 camcorder (records at 28Mbps), and am now looking at the SD cards I should get. I've narrowed it down to two: a Sandisk and a Transcend Sandisk Transcend The Sandisk has an advertised speed class of 2 (in product features) or 4 (in the picture) (which one should I believe?); while the Transcend comes in Class 10. I understand Class 10 would be faster, but why does it turn out to be cheaper? Am I missing something else? Thanks!