I’ve got a hero 3 black, I only use 960, 1080 resolutions generally and 1440 occasionally. I usually plump for around 30fps ish. I have used 60fps but it takes my PC that long to process I can’t be bothered and it’s not worth it for the minute bits possibly worth watching in slow motion.
As such, I could probably have got away with a lesser model.
Have a good look through the Abe Kislevitz site for GoPro settings and decide what you’d use and then select the model that suits best
My Hero 3 Black is was more than I ever use so probably wasted on me a bit in resolution terms.