I have a 15'6" Stratos bass boat that has a 40lb Minn-Kota bow mount hand control trolling motor on it. I have no trouble moving the boat when I put it on #3 speed and, when it's on #5, it will pull me thru just about anything.
I would recommend a bow mount simply because it seems easier to control the boat with, as opposed to a transom mount that will need a lot of input steering, especially when the wind is a factor.
Also, I only use my boat in freshwater, so that is another factor to look at. If you fish in the salt, look at a motor built for saltwater use, although it will be more expensive. Just my 2 cents... Rob