So far, all the commercial and 'truck' cam systems have had low resolution on all but one cam at best, and the sensors were a generation or two behind dashcams (which are also not 1st gen cutting edge technology). It seems like those systems aren't going to improve much, as they really aim to fill a slightly different role than what we use our cams for. And the security cam systems are in a similar place, as they needn't cope with high-speed movement. There's more to it than the hardware being used; for our purposes the only cams suitable are dashcams/action cams, or if you have the space a larger videocam meant for cinematic purposes (and those don't do well at night). But all is not lost
We've seen the 1st generation of 3-channel dashcams, and like any first effort there have been problems found with them. And Blackvue (or was it Thinkware?) announced at CES last year that they were working on a 4-channel cam which we might see within another year or less. The second generation of 3-channel cams is now beginning to emerge with the Viofo A139 which isn't going to be a huge step forward but is meant to address the discovered issues of the 1st gen cams, and from what I see at this point I think it's going to be the first truly viable 3-channel dashcam. I'm not free to say much more about it right now but I will say this:
If you want a 3-channel cam you should wait for it's market release which shouldn't be too far away. It is at worst going to be superior to these 1st gen efforts like the T3 and it might end up being more than that
I'm not sure where it will all end, but I think that is going to be a system with all-remote cams, a separate 'black box' processor with advanced cooling, and possibly even a separate module for memory which may not be in the form of SD cards. Each piece of the puzzle already exists in some form, so it's just up to somebody to put the pieces together well enough to get us the performance we need, while finding a way to do that at a marketable price. Dashcams have always developed incrementally rather than by leaps and bounds, and unless someone gets bold enough to jump this far ahead what I envision is still several years away.
Phil