rpgmaker
If you were looking for a class 10 microsd card in order to DIRECTLY transfer files from your PC to your phone the fastest way possible you can go with a cheaper class 4 instead of this one. The speed is not much different than other class 4 microsd cards I've had. It's very far from the 30mb/s they promise, I got only about 4.5mb/s AT MUCH, and after a few minutes it's downhill from there. I tested on both windows and linux and didn't see a difference. Luckily there's not a lot of difference in price between a high quality class 4 and this one but then again, maybe I didn't look at the class 4 the way I should have since I was focused on getting a class 10. Oh well, you've been warned. Don't expect magic from this card.UPDATE 12/11/2013: Sandisk proactively answered this review to ask me to contact them. The reason I didn't contact them first it's because you usually receive slimy answers from this tech support and hardly any solution or help. It is indeed a waste of time. After sandisk comment I contacted them through one of their live chat agents and this is the interchange. My suspicious were confirmed and I indeed wasted my time:Daniel S.: Hello, thank you for contacting SanDisk. My name is Daniel S.. Please give me a moment while I look into your question.fer da: heyfer da: i just got this answer from sandisk:  http://www.amazon.com/review/R3EMA7XPN7IDZD/ref=cm_cd_notf_message?ie=UTF8&cdForum;=FxFNZEI17MH7ND&cdPage;=1&cdThread;=Tx7VKC9UPWNI9X#Mx3FKEEV0WIILE3Daniel S.: Please tell me what is written on the face of the memory card?fer da: never thought of contacting you because i thought i was just going to waste my time, but it was nice to be contacted proactively by youfer da: okfer da: the same thing as the one on the picturefer da: sandisk ultrafer da: microsdhc Ifer da: 32gbDaniel S.: Please allow me a moment.fer da: will you need more info from the card?Daniel S.: The Sandisk Ultra card is a UHS-I card and provides optimum performances when used with a UHS-I enabled device or card reader.fer da: my phone is off.. lolfer da: it says that it is a class 10 card, i bought it because of the promise of better speeds than the regular class 4 when using it with my phoneDaniel S.: I would like to inform you that you will get the minimum read speed of 10 mbps on a UHS-I enable device as the card is built on the UHS-I technology.fer da: and write speeds?fer da: i'm getting like 4mb/sfer da: a far cry from the 30 MB/s2 promisedDaniel S.: I would like to inform you that so I said the card is built on the UHS-I technology it will give the optimum speed with an UHS-I enable device.Daniel S.: You will get the minimum write speed of 10 mbps with an UHS-I enable device.fer da: okfer da: waste of time confirmedDaniel S.: I would like to inform you that if you'll use this card with an UHS-I enable device it will give you the optimum speed as it's promise.Daniel S.: Is there anything else I may assist you with?***removed one star because of the sliminess of contacting me via amazon to show "sandisk cares" but not really offering any real support when contacted.