For HD video you need Class 6 cards or above, the K-01 hasn't the processor speed to make use of really fast cards, but you do reap the speed benefit when downloading your images to your computer. I have a 16gB UHS 1 card which can download a full card in under 3 minutes. You need USB 3 native on the motherboard of your computer and a USB 3 card reader get that speed.
The K-01 can use the UHS 1 card, but there's no increase in speed whilst it's in the camera, I don't get any more frames per second for example.
I use only Sandisk Extreme cards, these have several advantages (at a price) they are shockproof, totally waterproof and the X Ray machines at airports can't wipe your images no matter how much they turn it up. Sandisk Extreme and Ultra also have the advantage of being able to write to their controlling chip. Memory is paged on SD cards and if a page of memory corrupts the the card will automatically detect it and alter the control chip to use another page (all SD cards have spare memory) during POST (Power on Self Test) when the camera starts up. Lexar cards can also do this, cheap cards can't. Extreme 3 cards are guaranteed for life, if a card fails for any reason, including physical damage Sandisk will replace it. Never had to use it, but it's good to know it's there.
Chris
Last edited by ChrisJ; 09-03-2013 at 04:15 AM.