I have the Blueskysea B5M, it's about $130 USD off Ali Express. Here's an example video:
I'll never go without a dashcam, when I was a new rider on my SV650 I installed the cam and literally the next day someone didn't see me in their blind spot, merged into me, I locked up and went down. We didn't actually come into contact, just came super freaking close - the guy pulled over, then just left. From the camera I made out his plate and showed it to the police, who ultimately charged him and I got his insurance to pay for full repairs (most of which I pocketed, really it was just a clutch lever, shifter, and some chinese fairings).