Trolling Motor - 55 lb Terrova w/i-pilot or 70 lb PD w/i-pilot

Let me start off by saying that I have read the other forums about trolling motors, as well as read many other forums out there about the terrovas with i-pilot and the powerdrives with i-pilot. I believe I have a fairly good handle on the differences between the two. It appears that the terrova handles a bit better, is easier to deploy, and you can use the foot pedal with the i-pilot feature, which you cannot do with the powerdrive. All that being said, I'm looking to spend about $1200 on the unit itself (fairly large investment for me).

I believe I have it narrowed down to two choices - the 55lb terrova w/i-pilot or the 70lb powerdrive w/i-pilot. I have a 17'8" starcraft superfisherman (similar to the lund fisherman series) deep V boat. My question to those out there - will a 55lb terrova be enough power for my boat, or would I be better off with the 70lb powerdrive unit?

I primarily fish the Bay and Winnebago, so the motor will almost exclusively be used to pull harnesses. I had an old fiberglass boat that was slightly heavier than this one and had an early 90's powerdrive on it, 50lb, and it pulled it just fine on 8-9 power. As far as the differences on the functions between terrova and the powerdrive - easier to deploy, not so much an issue for me (my old one was very difficult and it still got me some fish), easier to turn (my old one was difficult to turn and it still got me some fish), but what I'm finding hard to overlook is that it seems that people absolutely swear by the terrovas over the powerdrives, which is why I'm considering slightly less power to go with a terrova and stay within my budget, versus the larger powerdrive.

Also, with the terrova, I could stay on a 12 volt system versus bumping up to a 24 volt system for the 70lb powerdrive. I don't believe this to be too big of an issue, but still something I have to take into consideration.

I appreciate your opinions as I have never fished with a terrova before. I have gotten some great advice on here in the past and am looking for some more! Thanks and good fishing.