Thanks for all the info. I think the salesman was trying to put into layman's terms the issues with wireless cameras.
That being said, I've been looking at the TadiBrothers 9" Mirror with Wireless 120° RV Backup Camera. http://www.tadibrothers.com/Catalog/BackupCameraKits/9-Mirror-with-Wireless-120-RV-Backup-Camera
I prefer to have the rear view mirror camera because I still look at the mirror out of habit, and I already have too many electronics on the dash. (GPS, TPMS, etc)
I have a real fear of drilling extra holes and tearing apart things IOT run more wires. Does anyone have experience with that system? What do you more knowledgeable folks think of it?
Thanks again for all the help.