I've always purchased Class 10 SD cards, because I like to do video with my GH2. But lately I've been doing some burst shooting (like exposure bracketing for HDR) and I've noticed some lag writing to the card, that prevents me from taking additional shots. Does anyone reading this care about that kind of thing, and has cards to suggest? Have you done any testing of cards? I don't think I'd want to pay the premium for those Sandisk Extreme or whatever they're called, but it would be nice to find a card that is slightly faster.