Just got done testing the read and write speeds of a new card from Sandisk called "Extreme Plus". Please note these are "SD" cards not "MicroSD". I tested against the traditional Extreme series of card rated at 45/45, Read/Write. The new Extreme Plus card is rated at 80/60. I was using Crystal Disk Mark 3.0.3 x64 for the tests. The standard extreme card came in at 46.19 MB/s read, and 42.14 MB/s write. The new Extreme Plus card came in at 87.66 MB/s read, and 73.23 MB/s write. both cards were 16GB models. needless to say I was pretty happy about that, considering the cost of the jump to go to Extreme Pro. I found the Plus cards sitting in the rack where the standard extreme cards were at my local Wal-Mart. They were $24.88ea. something tells me that price was marked wrong or not updated yet. Either way I photograph a lot of indoor Roller Derby with my D600 and the old cards would catch me sometimes with writing time preventing me from getting some shots. I hope this really is the "affordable" cure I was looking for.