If you want to stick with name brand cards here's a deal on Lexar 64GB SDXC Professional Class 10 600x UHS-I Memory Cards. Regular price $69.95, save an additional -$27 dollars OFF.
These cards are fast enough to support 4K video from the new GH4 and 1080p at 200Mb/s. For a limited time these 64GB 600x SDXC cards are now just $42.95 (found here).
Lexar 64GB 600x SDXC Media Cards
jonatani
The price has gone up to 50.95 as of today. Not buying it this time.
Johnny
Another sd card that I use a lot is Komputerbay. Fast enough for 4k recording. https://smile.amazon.com/Komputerbay-Secure-Digital-Extended-Capacity/dp/B008AN1C1A/ref=sr_1_1?ie=UTF8&qid=1401279078&sr=8-1&keywords=komputerbay+128gb
Habez
@stanperry If im not wrong, these SD cards shouldn't be fast enough to record raw in the 5d3 with the magic lantern hack not because the SD cards are too slow but more so because the card writer in the camera itself can't keep up with the speeds.
Thats why the magic lantern community always recommends using a x1000 speed *CF* card for the raw hack in the 5d3.
Side note: Things might have been updated since i last checked so i might possibly be wrong if there have been new developments on that front.
Emm
Post author@stan perry - It sounds like it is fast enough. I believe you just need a write speed of 25MB/s for Magic Lantern, and these cards have a minimum of 45MB/s.
stan perry
what about shooting raw with mark 3 ?
Emm
Post author@Eric Benson - These do not work with the BlackMagic Pocket Cinema Camera.
Eric Benson
Do these work with the pocket camera?