We looked at all of the models but settled and installed one of these systems from www.rvrearviewcamera.com
Be sure and check out the video on their website (heading 'real life video' or something like that).
The kit establishes a digital, wireless hot spot with ~60' range with camera and router and router to your smartphone as the monitor.
Easy to install (software included) and the only brief (1-2 sec) loss of picture interference is when completely stopped at a intersection with traffic light-police installed "traffic" camera.
Otherwise, no issues in town or with other vehicles with their own camera system. Good luck with your selection.