[twitch]

I was using my K-5 in Hi burst mode on the weekend, and for the first time using a new Lexar Class 6 Platinum II 32GB card. Damn the read/write was slow The high bust speed was just stunningly fast though at least while there was buffer free.

I managed to fill the buffer a couple of times and it took forever to clear it. Also I stopped even trying to review any shots as it took seconds from pushing play to getting an image up. Even in single shot mode it takes a few seconds to review a pic.

I need to figure out if this is a slow card issue, or a "high burst rate, large RAW file" K-5 related issue. It sure made me want a top quality class 10 card though

I never noticed this problem with my K-x & Sandisk Extreme III cards.

[sany]

Like most of the response above - no matter which brand you go for atleast try to settle anything above Class 6 or if you don't mind spending go for class 10. I am using a 16GB class 6 in my K-r, so for no issues.
I need to stress once again on the class of the SD card more, still there are many cards out there that does not even mention anything about the type of class on their label (many cards that will be usually part of a discount sale etc.,, you can right away reject those as these will most probably from unknown or smaller known brands and they are mostly class 4 or less.
Because of the absence of the type of class missing in some of them, many people have doubts as to where it will be printed and to help that here is a sample image where you see the type of class, this will totally be missing in those shady ones. There will be a number in a broken circle imprinted and sometimes it will read as 'class' followed by a number inside a broken circle, in the image below the number 6 signifies the type of card.

Originally there used to be only these 3 Classes and Class 6 used to be the premium out of the three, so Class 6 should do fine unless you have enough room in your budget for storage.

Additionally to the above, I thought it would be helpful for someone if I extend it to have some word about SD card readers (which I wrote in our corporate staff newsletter more than a year ago - this can go as a sticky somewhere if the moderator wishes)

Don't be surprised if your 8GB SD cards won't work in the device that was used to play your 2GB SD cards all these years. If you note carefully these are SD HC (High Capacity) cards and not the normal SD cards that you have been using. The capacity for these new SD HC cards can go around 32 GB maximum (as of last year, don't know the new progress with the technology) and soon you will notice this in the market displays. Before you buy these SD HC cards please make sure that your device manual lists compatibility for SD HC card (of course yes your DSLR now supports - this could be useful to check with you image accessing devices like your PCs and Card readers) along with the other compatible devices or it should at least state that the device is "SD specification 2.00 compatible."
Most new devices these days however are SD HC compatible. If you are using a Windows XP laptop that was bought sometime back with multi card/SD card slots and your machine cannot read/write these new SD HC cards, then don't worry - 'hot fix' is now available on the Microsoft website here The 923293 hotfix adds support for SD High Capacity memory cards in Windows XP. Similar updates are available for Windows Vista machines.

As a last comment: Just notice somebody mentioning the investment in SD card is kind of investing in lens but I would say SD cards have life to them, as you read and write it wears or some sectors tend to get corrupt. So the investment in the card is not forever. But it is wise to buy a well branded card like Sandisk etc.,

[JinDesu]

Transcend Class 10 is a very good card, and I see it on sale very often.

[Tabasco]

Hi there if u want to use microsd card with sd card Adaptor in pentax k-r do the following instruction.

1. Save ur photos of the microsd card cause u will lost it when u format it.
2. Put the Micro sd card in the computer and format it to NTFS.
3. Put the Micro sd card in the pentax k-r and turn it on.
4. It will show on the display the message "card not formatted"
5. Format the card from the pentax k-r menu.
After u done.

[Anarethos]

I bought a Toshiba 64gb FlashAir (wanted the Wifi option) and it works flawlessly.

I let the card in the ExFAT format and it works with firmware 1.14.