I have a drift ghost s and a GoPro hero 3 silver.
They are 2 very different things to be honest.
Drift will work for vlogs straight out of the box with a external mic, is easier to mount and has a smaller profile on the helmet. Never had a single issue with crashing have only had a crackle issue which was a damaged mic.
GoPro will give slightly better results but will take a lot more work to setup. Currently have mine mounted on the bars and it suffers from jello wobble.
The other thing I have found is once the videos are processed, and loaded to YouTube you can't tell the difference.
You can check my xmas video as there is footage from both on that. GoPro does need some settings changed as for some reason it was quite washed out.