I've just bought the 70 lb Power Drive for my new boat on order. The Power Drive is the older version of the Terrova. If you need more than 70 lbs you need to move up to the Terrova. I had one of these years ago and liked it then. You are correct, it is very responsive in fact probably as fast as you can move the motor head on a traditional foot control. I got mine with the autopilot, the built-in dual beam transducer, and the add-on co-pilot. The autopilot uses an internal compass to automatically keep the boat headed in a compass direction. The co-pilot is just a remote wireless key type fob. Minn-Kota also offers another option which uses GPS (don't know what they call this)which although has been out for at least a year or two, I've read and heard bad things about this. It's suppose to keep the boat in the same place regardless of wind and current. I've heard that in some cases the boat just spins in circles. This kinda of makes sense in that GPS readings can be 3 meters off so if the reading keeps changing I could see how this would confuse the motor.
If others have had success with the GPS I would like to hear regarding this as I can always add it.
Also we were at the KC Sportshow a couple weeks back and I noted that the Terrova was on some big Ranger boats.