Pretty nice prices on high end sony memory. I believe these are all u3 qualified with minimum write speeds around 45-50MB/s which makes them good for 4K video and such

90MB/s

• Sony 64GB 70MB/s Class 10 SDXC Memory Card [focuscamera.com] $15.99
• Sony 32GB Class 10 UHS-1 Micro SDHC 70MB/s Memory Card [focuscamera.com] $8.49
• Sony 32GB Class 10 UHS-1/U3 SDHC 94MB/s Memory Card [focuscamera.com] $11.49
• Sony 64GB 94MB/s Class 10 UHS-1/U3 SDXC Memory Card [focuscamera.com] $24.99
• Sony 128GB Class 10 UHS-1/U3 SDXC 94MB/s Memory Card [focuscamera.com] $44.99
• Sony 256GB Class 10 UHS-1/U3 SDXC 94MB/s Memory Card [focuscamera.com] $92.99
• Sony 32GB UHS-1 SDHC Memory Card [focuscamera.com] $16.99
• SONY 64GB SDXC CLASS 10 UHS-1 R95 Memory Card [focuscamera.com] $29.99

• Sony 32GB Class 10 70MB/s SDHC Memory Card [focuscamera.com] $7.99
• Sony 32GB SDHC Class 10 UHS-1 Memory Cards (2-Pack) [focuscamera.com] $13.99
• Sony 64GB 70MB/s Class 10 SDXC Memory Card [focuscamera.com] $15.99
• Sony 64GB SDXC Class 10 UHS-1 Memory Cards (2-Pack) [focuscamera.com] $25.99
• Sony 128GB Class 10 UHS-1 SDXC up to 70MB/s Memory Card [focuscamera.com] $27.99
• Sony 128GB Class 10 UHS-1 SDXC Memory Card (4-Pack) [focuscamera.com] $99.99
• Sony 32GB microSDHC Class 10 UHS-1 Memory Cards (2-Pack) [focuscamera.com] $15.99
• Sony 64GB microSDXC Class 10 UHS-1 Memory Cards (2-Pack) [focuscamera.com] $28.99