Ken, I guess it would be too much trouble to take your control head with you? That would eliminate any discrepancies except electronic compass which I'm real sure is the same. The good news is the 'X-5' course computer has all screw fastened terminations that you are for sure aware of, but the reason I assume them to be more or less identical is I one time tried a 6000 computer with an X5 head and it worked. The only difference I could ascertain was the aforementioned Seatalk, and Seatalk Next Gen. But the new Ray auto's come out of the box with Seatalk cables, (with the NMEA-2000 stuff), to hook up these older accessories. Even NMEA-0183.
You know, for all the bad rap I hear about Raymarine, I seem to have little problems with their stuff, aside from my obvious stupidity in application albeit. I know some functions are not exactly to my taste, like the autotack maybe could use some tweaking, etc. It also won't back my boat out of the slip either..