Welcome to the party Captain.
If you are hell bend on a American made product, then that rule out just about all commercial grade dashcams.
If customer care and support are high on your list that pretty much narrow the field down to street guardian, their approach to those matters are second to none in this field and a lot better than you will find in other fields of consumer electronics.
Not that its much needed, but if you are unlucky with a SG product the boss himself and a worldwide network of resellers will jump as soon as they get the chance
Street Guardian are a Australian brand, but they do build their cameras in China, but they have standards and so their cameras are not among the cheapest of cameras out there, by now SG do have both a cheap and med and high end solutions, but still none of them are
cheap cuz cheap dont mean Chinese cheap for this Aussie brand.
Many of us addicts have full coverage ( 4 cameras ) and some of us even more, but up until now such systems more or less had to be made up of several single cameras, but things are moving forward and this year 2017/18 are the first season where you can get worthwhile dual-channel systems so with 2 sets you can cover all 4 sides and you only have 2 memory cards where the footage are stored Vs 4 if you have single cameras.
Next year i think we will start to see worthwhile quad channel systems, the components are already there but makers have not yet pulled the trigger on such systems, i think they bite the bullet and wait and see how dual channel systems will sell.
You can also find other brands that can deliver the same grade of footage and you might even find those a bit cheaper, but they will not have the customer response SG have as far as i can tell.
Normally in here if you post in the SG subforums and its a problem or for that matter pretty much anything the response time from a official SG person are measured in minutes most of the time.