Update to this thread....
Since I have a boat on order (Tracker Pro Guide V16SC) and it will be here soon, I will now be testing the iMK Powerdrive that is included with my new boat. It is a 12V 42# 55" shaft without spot lock (GPS).
I'm not sure how well the 42# is going to do, as it is fairly heavy boat at 1170# dry weight (manufacture specs).
I purchased a Lowrance HDS Live so a MG would now be my choice as the two communicate well.
That being said....
After I test out the MK TM, I'll decide if it's worth adding spot lock for ($500).....OR getting a more powerful MG TM.
Since I troll at 2mph for 90% of my use (with 1-3 anglers aboard).....
I'll need to decide if a 12V or 24V is the way to go. I hate the added weight of two batteries, but everything is a trade off. Even if I had a 12V, I would probably run 2 12V batts in parallel for the added troll time. if I did that, then a 24V TM may the preferred option. I'll post a new thread on 12V vs 24V once I test the new TM.
Thanks for all of your input, as it will be very helpful even with the new heavier boat!