I have a gopro hero, bought a few years back. Basically a stripped down hero 4 with no screen/wifi. At the time this was only £99 new, but it seems their current equivalent, the session, is somewhat more expensive. I find the lack of screen a non-issue as if you're always snapping it back into a mount which hasn't moved, you always get the same view. Just a few test videos and pop the SD card out to check to get aligned initially. Quality of image is great and its a sturdy piece of kit, used for activities from snorkeling to snowboarding, never skipped a beat. Maybe worth looking for a used one on ebay? Even though mine has had some use, because its robust, it will go on for a long time yet. I dare say there are plenty out there which have been used a handful of times and then shelved.