Like I said, it's more important to get a card that fits within your budget and has a good distro that handles RMA nicely.
Of course, if you have the money to burn, by all means go for the higher cards, there's absolutely nothing wrong with that, just that you are likely wasting money on those speed claims which you will not benefit from.
Those who have been using Samsung probably knows that Samsung has this weird habit of killing SD cards... based on feedback gathered, those on Class 6 and below don't get it, those on Class 10 and above appears to get it more frequently.... but again, it's all luck, since no one has been able to correctly pinpoint the problem or brand. This is why it is more important to get cards from a good distro which are efficient with their RMA process.
For those who believe the myth that Samsung cards are better(as in they won't die off that easily, speed wise they are the clear winners), do ask Samsung on what is their stance on warranty and claims for their SD Cards, since there are alot of parallel imports locally.