I don't have one but I've also been casually shopping them for a few years now. They're never quite high enough priority for me to put them at the top of my shopping list, which I know is a sense of complacency that I should get over.
Anyway, Viofo if you want something affordable with good video quality.
Thinkware or BlackVue if you want to go with premium 2-channel (front and rear) 4K options with Wi-Fi, app control, and optional accessories like auxiliary power and idle battery drain cutoff. I've been thinking of one of these in a 2K/1440p resolution.
At one point before I understood dashcams better, I was wondering whether there was some kind of custom multi-channel front-facing setup you could put together to use as a track cam, but realistically for that, just get a GoPro or other action camera and mount it to your bumper when you need/want it. We have a tendency to believe that we'll start capturing all kinds of interesting things once we have cameras running, but the vast majority of the footage you'll collect is utterly boring and not worth keeping.