I have a terrova on my walleye tournament boat. That being said, I just put a brand new Ulterra on my dad's new boat. The reason for it was that I do not want him to have to or need to move up to the front of the bow and deploy the motor in rough seas. I don't want my mom to have to do it either.
A couple things I have seen right off the bat:
First, the head unit is no where near as solid as a terrova. There is a ton of slop in the shaft when it is stowed. I purchased a RAM mount to combat this when it is being trailered or when moving from spot to spot. This I don't like as the whole purpose was to NOT have to go to the bow of the boat.
I trust that they have issues worked out but, it is mechanical after all and we know everything mechanical CAN break. I would suggest putting a battery meter in place (not just the one on the unit) in order to monitor. In the event you troll all day long (like we do) I would be concerned with running out of battery. In the event you deplete the battery, the only option you have to stow the unit is to utilize the manual bypass. When this is done, the motor is no longer able to be utilized as intended and MUST be shipped to the factory or to a service center to be reset so that the electronics can be used again.
The power button MUST be turned on. Unlike a terrova where the power is on when you hit the button, the Ulterra must have power to the unit at all times in order to make it work. So, when you get in the boat, plug in the unit, you need to hit the power button. Otherwise, you are walking to the front of the boat to turn it on when you need it. Again, no point in having it if you have to go up there anyway.
Read the instructions: What one would assume to do in order to deploy the motor is NOT what actually happens. IE, you don't hit the deploy button once to deploy it, you hit it twice. To stow, you hit the button once. Seems backwards to me. I've accidentally hit a button or two while trolling. The last thing I need is to hit that while trolling and stow the motor.
If you can get past these little things I have noticed, I would say go for it. Is it working as intended for my parents? Yes. Dad is almost 70, has bad shoulders and two replaced hips. Mom has a replaced hip and knee. The last thing I need is them to be in the bow of the boat. IF there is an issue with it, I'll cross that bridge when I come to it. I hope this helps.