I use a Minnkota 55lb. thrust on my 17' sailboat. No fixed keel
though. We move along at about 3knts. The nice thing is that it is whisper quiet and there is no odor
. We replaced a 1968 Johnson 2hp 2 cycle...
The bad news is that in some rough conditions that we ran into late in the season it could barely push us where we needed to go (to windward). The chop and wind
were too much for the little guy.
Overall for us it has been fine though, the farthest we motored was about 4 miles one day when the wind completely dropped off on the lake. Usually we just use it to get away from the launch and back in.
But, like I said to start our boat is smaller and lighter. Good luck!