I have 2 of these systems, one on a street bike and one on a dirt bike. I like to capture videos of my rides and I have had issues with helmet cams and their battery life. When I found this setup it got rid of that problem. The front and back camera adds a whole new dimension.
Also the ability to control the length of the videos and also being able to take photos is a great plus. I hooked mine up to a switch so I can control when it is on. I use a 128GB card and it's amazing how many videos fit on it. I just got back from a 4 day ride on my dirt bike and I only used 64GB. I used 1 minute video length and each file contains the date and time as well as which camera it is, which makes it really easy to find a certain video.
The microphone is in the switch that allows you to take photos, and it can get a little noisy depending on where you mount it, but it's not a big deal.
IMO, this is a must have, and it's a lot of value for the price.