PLEASE NOTE: This review refers to the Samsung _32 GB_ Micro SDHC MB-MSBGAEU _bought directly from AMAZON UK_, and not to any other smaller or different Samsung card sold by any other marketplace seller or even on Amazon. It is important to understand that there are LOTS of fake cards on the market, which might be defective, and other Samsung cards with smaller sizes or different models, which might have completely different performances, so beware what you are buying...!
First things first: as I wrote in my review of a Transcend 8 GB Class 10 SDHC card, I have always been wary of extremely large flash memories, for obvious reasons: unreliability (documented by many Amazon reviewers around the world...), high failure rate, and the extremely likely danger of losing huge amounts of precious data _all at once_, especially when these cards are used for long, sustained data transfers that might raise their temperatures too much...
Moreover, the very high cost of high-capacity, Class 10 Micro SDHC cards _so far_ in my opinion made their purchase not convenient at all...
Nevertheless, in the last year the price of these memories has dropped so much, and their performance and reliability have improved at such a level, that I decided to take the plunge and risk my hard-earned money on this one, since I had decided to transfer my entire, huge collection of thousands on MP3, picture and video files on my Samsung S8500 phone (IMHO a perfect portable multimedia platform to enjoy all such contents).
I chose this specific card not only for obvious compatibility reasons with my phone, but also because Samsung is among the top producers of solid-state memories in the world, and has a proved record of high performance, reliable memories.
Moreover, this is a new product that was supposedly _designed_ to match the features of recent phones, tablets, etc.: it is magnet proof (so no harmful magnetic interference inside the devices), shock proof (so no danger of losing data due to falls, in theory) and even water proof (I hope I will never have to verify that...), and it should provide adequate performances, including a _decent read/write speed with small files_, which is extremely important on such devices, especially if you install system programs/files on the external card instead of the built-in memory, as I do.
So, if you want to know right now how this card behaved in a typical PC benchmark, I tried to use one on the empty card after formatting it on my phone, and I immediately obtained _great_ results, even while using the system, browsing Internet, moving the mouse, etc.: as a matter of fact, the typical test methodologies often assume the absence of any cuncurrent operations, perfectly "clean" systems that _nobody would use_ in the real world, "safe" operations that no real user would probably be able to apply day-to-day, etc., while I always apply a _realistic_ average-user behaviour, instead...
WRITING SPEED (MUCH more important than read speed, since it is the writing speed that can be the real bottleneck of any device, either when you write system files on the card, or if you have to index lots of files, or if you simply want to record movies, music, pictures, etc. on it.)
Approx. 8-10 MB/sec. with files within 7-32 MB sizes (very good, between nominal Class 8 and actual Class 10)
Approx. 4.7 MB/sec. with 256-KB files (again, pretty decent for a card of this class and especially at this very low price...)
Approx. "ONLY" 1 MB/sec. with 32-KB files (BEWARE: this might slow down some systems, but it is quite normal on huge cards with higher classes, since these cards are specifically engineered to provide high speeds _only with larger files_, while smaller cards with lower classes (4 to 6) behave much better with smaller files.
These were really great, IMHO! (And basically matched what was promised by the manufacturer):
Approx. 20 MB/sec. with files of 64 MB size
Approx. 10 MB/sec. with files of 7 MB size
Approx. 16 MB/sec. with files of 256 KB size
Approx. 6.7 MB/sec. with files of 32 KB size (I think this is REALLY good for a Class 10 on such little files...)
Anyway, as I explained in my other review, these "theoretical" results mean almost NOTHING to me, so, I immediately tested the card using the exact same _personal_ REAL-WORLD "torture test" I used with other cards, i.e transferring huge amounts of data of all sorts in read/write modes and simply _timing_ them, and stressing the memory card savagely FROM MY DEVICES, while actually _using_ them.
The results were VERY good, in my opinion, given the prices of this card:
I wrote 10.057 FILES (!) of ALL sizes and kinds, for a combined size of 15.3 GB using a Transcend S5 reader on my PC WHILE USING IT (e-mail, mouse, web, etc.), and it took 29 minutes and 30 seconds, which means a _combined_ _writing_ speed of approx. 8,65 MB/sec. Considering the tons of small system files included in the test, this was a very, very good result, IMHO.
But I was not satisfied, so I immediately deleted everything and transferred approx. 28.8 GB (!) of assorted data, including phone system files, 5000 MP3 and jpeg files of all sizes, _without letting rest the card_, and this took 49 minutes and 32 seconds, which means 9.7 MB/sec., even BETTER THAN THE FIRST RESULT! (This way I also tested the full capacity of the card, which was very important. Please note that the full formatted FAT 32 capacity of this card is approx. 29 GB, not 32, of course).
Finally, with the card almost full, I wrote ALSO a single 816-MB file, and it took slightly more than 100 seconds, which means again 8 MB per second approximately, a consistent result with the previous ones, considering that often the last memory areas of large cards are also the slowest ones.
Therefore, IMHO this card performs consistently as a Class 8-10, and this is much more than I expected at this price range. I installed dozens of games, which worked all flawlessly from the card, and my phone was able to index 5000 mp3 in _thirty seconds_ on it, which is much faster than my previous 16-GB Class 6 card, again a great result.
I also shot an HD video at 1280 x 800 pixels for several minutes, with the card almost full, and it did not show any "hiccups", it never slowed down, and the result was again perfect. (This also depends on the phone, of course, I have no idea how this card would behave in other devices, sorry.)
Naturally, I CANNOT TELL ANYTHING ABOUT THE RELIABILITY OF THIS CARD, for the simple reason that I NEVER used Samsung cards before, this is a brand new product, and it will take _months_ of everyday use to find possibile defects/flaws/issues, of course...
So, the only question is: will it last? Many large flash memories die after a few weeks or months, and only time will tell, so I will update this review immediately in case it dies on me too.
So far, this card proved to be huge bargain, compared to much more costly brands, and it demonstrated once again that you DO NOT ALWAYS NEED to spend a fortune to get great performances; I am crossing my fingers on reliability! ;-)