Re: Speed/Depth/Wind conundrum
We've got the SH 180i, happy with it but it needed a chip and the resolution is somewhat wanting at certain zoom levels. But it's working. I understand the newest versions include chart files, but check that out.
If you want to talk to Raymarine you're probably better off with an integrated system on Seatalk rather than trying to interface different brands via NMEA.. though that's generally doable too. Raymarine has some nice $5-600 plotters, not sure how much the depth feature tacks on.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"