I have an M802 and like it a lot. I use it on the ham bands for
email on winlink. I have an SGC tuner which I am also pleased with; I bought it to use with my old ham
radio, before switching to the
Icom. The Icom tuner has the advantage of being integrated, so there is "handshaking" going on between the radio and tuner. The SGC just senses the first
transmission and tunes it up, indicating tune on an LED. Some think it is a better tuner. I suspect either would
work just fine.
Yes, the Dynaplates I have are a problem. They crud up. One of them is breaking apart. Anecdotal evidence suggests they only work for 6-9 months in the
water, then must be removed and soaked in acid. Not impressed...
I wrapped the underwater portion of my transom-hung
rudder with roofing copper - it has proven to be an excellent ground. If you are interested I can explain how to do it.
I have an insulated backstay as well. It seems to work well. I have some reason to think that a vertical multiband whip
antenna might perform a bit better. With the M802 it is desirable to have two antennas (I don't yet); one for the transceiver and the other for the
DSC receiver. So I may add a whip and switch between them to see which works better (don't hold your breath: if I do it, it will be a few years from now).
Winlink works for
email, including grib files. It is free, but requires getting a ham
license. I recommend doing that. Otherwise stick to the
marine bands and paying for the Sailmail
service; it uses the same
software but has far fewer land stations.
Good luck,
Greg