S1 upgrade - FYI
I bought an S1 last summer, but I have not installed it yet, as it requires the rudder sensor. I asked Raymarine about upgrading it and they said if I sent back the main controller and $400 they would upgrade the S1 to the X-5, without the need for the rudder sensor.
I got the S1 on sale and I think the rudder sensor is probably a good idea, things work better with feedback. So I did not follow up on their offer. My biggest problem is that the boat is in NC and I am still working in NJ. So, someday soon I will get to it.