I have the 80lb I pilot.  Its a great unit!  My suggestion is to go with the terrova over the V2. 

pony up and get an 80lb Terrova with I-pilot.  Nobody really has a significant savings over one another.  Cabelas has free shipping, Scheels has them in stock for same price, and maybe a factory rebate going on right now too.  This technology has made such a difference in fishing that I think that you would regret buying anything less down the road.  For example, look how many trolling motors are for sale on Bisman right now.  All those people that are selling those because they bought the I-pilot.(Well, most of them).  If you can't fork out the cash right now I would limp the old motor along until you can afford it.  Just my opinion.

I have a 70lb V2 with I-pilot and the old man has a Terrova 80 with I-pilot.  Both very nice units with good power and the hand held control works well.  If you like to use a foot pedal you will need the Terrova because the V2 I-pilot has no foot control.  I hate foot controls so the V2 works just fine for me.  I can't really tell any difference between the units as far as power.  I have an 80lb Vantage on the back and the 70lb unit on the front will troll just as fast on high.  The thing I like about the V2 is that there is a deploy lever you push on with your foot that helps you get the motor out of the store position which saves a lot of cussing trying to get the motor down.  Both good units.  I would just pony up and get one of these, as they are pretty darn nice.

Oh, and if you keep checking Amazon, you can catch a great deal and not have to pay sales tax.  I paid  $900 for my V2 without sales tax. 

depends on the size of your boat, I use a 101lb terrova 36 volt, on a pro v 20 ft. Better to have to much power and battery reserve than not enough. I can usually fish for 2 days on one charge, and if the wind is blowing like it of course always is in ND you will have no prob with boat control.

The boat is a Lund 1800 Fisherman, 1993 version with 115hp Mariner and 15 hp kicker. 

I would go with a 24v 80lb thrust terrova

I have a Terrova with I-Pilot 80lb thrust on my 18.5 G3 and it pulls the boat around all day and then some.

Very happy with the Terrova 80lb iPilot on my Alumacraft TP 175