I use a Simrad TP-32, installed in 2013 to replace an earlier
Navico TP5500 and provide NMEA2000 connectivity.
It has worked very well to follow routes under
power during summer cruises in the light-air
Pacific Northwest. It plays well with my
B&G MFD and also with
OpenCPN on a PC.
It also works well under sail in light conditions. However, in heavy air I wouldn't rely on any electric-powered tiller
steering unit--the pin-connection to the tiller isn't very robust, the
power draw is significant, and the heavy steering forces would likely wear out the
motor rapidly. A proper
wind vane steering system would be preferable.