I'm surprised that so far, no one thinks putting a dedicated, always on rear view camera on the back of the TT is not better than trailer tow side view mirrors.
As I understand the geometry, pushing the side view mirrors out an extra 4-6 inches simply reduces the size of the blind spot behind the TT. On a 30 foot trailer, I suspect a Kia or other small vehicle could still hide back there.
Additionally, having the camera, because of its field of view, would make passing safer by providing confirmation that you have cleared the other vehicle - if you can see the front bumper of the other vehicle on the monitor, it has to be behind the trailer.
I have investigated getting the manufacturers tow mirrors installed. To do so, in addition to buying the mirrors - in both doors, the wire harnesses, switches, and control modules need to be replaced. Dashboard fascia needs to be changed for the new extend switch, and a main control module needs to be flashed with info from another truck that has the mirrors (if they can find a truck to copy from). Geez, these computer controllers are a pain.
So this is a VERY costly effort and probably significantly more than buying the camera system. Yes a set of CIPA's or similar could be used, but I've seen lots of complaints that they damage the mirrors they are mounted on. One guy lined his add-ons with felt in an effort to prevent scratching.
Finally, while I would prefer to have different tires and may change them sooner rather than later, EVERYTHING needed to tow a 10K+ trailer IS on the truck - I've checked.
So why doesn't anyone think the camera option is at least as good a solution as extendible side tow mirrors?