I am using a Polaroid 16gb HC micros SD card class 2. I purchased it at Fry's Electronic Store for $29 (sale). I am using 8gigs currently- this includes documents, music, movies (4 full length movies), short videos 30 min (20), apps and yes, smartgear and game roms (10 games). I have been using this card for half a year now with NO issues, lags or problems. Also it does not waste my battery- can watch a full length movie and some.
Ebay lists a Sandisk 16gb for $34.45, new, free delivery.
16gb Kingston bundle at Fry's $62.99
http://www.frys.com/product/5976284?...H:MAIN_RSLT_PG
Panasonic 16gb card $27 after rebate ($42 regular) at Fry's
http://www.frys.com/product/5885833?...H:MAIN_RSLT_PG
A brief description about selecting the type of class for your SD card
http://www.funtechtalk.com/sdhc-card...ss-mean-2-4-6/
Hope it was helpful...