When the wife and I are shooting wildlife, we often are using high speed frame rates....and we only shoot raw format. So we wanted large and fast cards to minimize needing to change cards during an action sequence. Today I received a pair of PNY 256GB SDXC Class 10 cards (P-SDX256U1H-GE). I put them in my rMBP's SD slot and ran BlackMagic Disk Speed Test on them. The write speed averaged in the low 60s with reads in the mid 80s. I compared that to my previous card which is a Lexar 64GB SDXC 600x card. The Lexar averaged in the mid 40s for writes with reads in the low 80s. The PNY card was $99 at MacMall which was cheaper than B&H even after I paid GA sales TX. So if you want a large, fast SDXC card for under $100, you might want to consider the PNY 256GB Class 10 model. They could be very nice stocking stuffers!