The phone only supports up to 32 GB cards, unfortunately. There really is a dizzying array of cards on the market, but most of the cards I see that are above class 4 seem to be either mislabeled or just plain untrustworthy. There's a SanDisk 32GB Class 4 on Amazon for $27 that might be the best deal that I've found so far
If you guys go to nextag.com and enter 32gb micro sdhc class 10, you'll get brand name cards like PNY, Transcend,Lexar, etc. listed for ~$35-$40. That's the best consistent price I have seen. Just some info for you if you weren't familiar with Nextag.
From the reviews I have seen you would be better off to avoid Komputerbay.
I've got the Samsung class 10 from kumputerbay. Seems to be up to par in my rocket, only took one day to arrive. (make sure you use the drop down and select Class 10 Samsung). Definitely pays to have Prime.
Samsung BlackJack 2 (ever reliable)
Samsung Mythic (Wouldn't wish it on my worst enemy)
Samsung Captivate (problematic)
Samsung Infuse (Great day to day use phone, first since BlackJack 2 with no major issues)
Samsung SGS2 LTE Skyrocket (Pretty cool, drained a lot of battery.)
Samsung SGS3 (Got a free upgrade. No issues with it all. In my opinion, the first polished smartphone)
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