Sony FDR X3000 – Better Than GoPro Outdoor Gadgets / Action Camera, GoPro Killer Better low light performance, built-in optical stabilisation, sharper, and higher bitrate.
YI 4K Action Camera better than GoPro? Outdoor Gadgets / Action Camera, GoPro, GoPro Hero4 Black, GoPro Killer, Yi, Yi 4K Better than GoPro or at least close to it at half the price.