I upgraded to the Ultrex 36v 112 from a 24v 70 on a 20'foot boat. Night and day difference. IN the same wind conditions i would have to run the 70LB motor in the 70% -100% power setting i can now run the 112 in the 30% - 60% power setting.
As for the Ultrex features, way way nice. Spot lock is awesome. Catch fish hit a bottom stay on spot. Break off, hit button and retie..find a brush pile or hump....you get it. Ipilot works great too.
Long term reliability report is still TBD as i have just had it a short time. Waited 2 months for mine to come in but i was tied to one retailer due to having lots of gift cards..