Unfortunately, you can't look at class, only. If it's a some no-name brand, it doesn't matter if it's a class 10. It probably won't perform at the advertised speeds. Or if it does, it probably won't last long. Unfortunately, Matt had a really good card, but must have gotten a lemon. The patriot 16 GB class 10 card is a good choice (albeit a bit expensive). I have the same card, and it works fine, so I will still recommend it. I won't blame Matt for getting something different next time, though. I will agree, also, that you'll want at least a class 6 for a2sd. A class 2, even if it's a high quality card, probably won't be good enough for that. It *could* write much faster, but it won't be rated as such.