Is the ultrex that much better than the terrova.
That is a personal decision. The Terrova does everything that the ultrex does except has electronic steer foot control instead of cable steer. I chose to take an Ulterra over the Ultrex for the auto deploy and stow feature and have not regretted it once. Prior to that I ran Terrovas for the last several years. no one can honestly tell you that one is better than the other for you unless they know how you prefer to fish with it.
I personally would take the trolling motor over your other two options.