I'll first go into reliability. I have had one Motorguide Xi5 gps head unit crap out on me. Motor worked fine, but GPS died 6 months outside of warranty, fortunately it was the one and only time I've ever had an extended warranty on anything (bass pro) and they made it right. I've also killed a Minn Kota Terrova GPS head unit. That one wasn't under warranty, and I got lucky with a Canadian Tire clearance deal when they were still carrying the ipilots and I replaced the head and remote for a few hundred, otherwise the repair would've been in excess of $600. My Terrova is currently at Aikman's Sporting goods getting the brushes and seals replaced because it sounded like someone wash beating on dog squeaky toy with a hammer every time I turned it on. Minn Kotas, even the Terrovas aren't bullet proof by any means. I've had many issues with pedals, head units not turning, replaced a board on one once etc on Minn Kotas over the years. They all have issues. The Xi5 was a pretty sweet motor for the 3 years I had it. The replacement got moved on with my old boat. I guess if I had to pick it would be a Minn Kota. However Aikman's just told me that the last gen pre Bluetooth the motherboards have been discontinued now. Keep that in mind when buying used. As for your boat, a 55lb will work, but yeah wind will occasionally be a pain in the butt. If you troll a lot and use the motor to steer, you'll kill even a group 31 after about 6 hours. Flat dead, and the more you do that the shorter lifespan of the battery. I used to get about 2, maybe 3 seasons of heavy use on a 31 series with a 55lb thrust on my 16 footer with constant trolling. If you can swing it weight wise, I'd try to go 24 volt. Just my 2 bits.