The tiny “4K Ready” camera from Sony - the PXW-X70 has been proving quite popular with documentary and event shooters given its small form factor. Apart from its size, the other most impressive feature in my opinion is the 10bit 422 Long-GOP codec and the fact that you can upgrade the camera to shoot 4K with the upcoming (paid) firmware in June, thus future-proofing your purchase.
Powering your ENG or large sensor camcorder for prolonged times does require a solid and reliable battery system. Anton Bauer and V-mount have been established standards for many decades and there are numerous manufacturers offering different battery solutions to camera professionals. However, just as with anything in video technology nowadays, batteries evolve and improve and not all batteries are made the same, and choosing the right battery solution for your requirements can be difficult.