Hi Doug,
I have gone through the same issues over the years and have had several brands, i.e. in chronological order 2 force 10, 1 Magma, 1 Kuuma and for the last 4 years the smaller of the 2 SeaBQ models by Dickinson. I love the way the SeaBQ is fixed to the railing and can be easily removed. I also like the fact that the grill is in 4 sections and can be removed easily for cleaning. I don't care much for the idea that the finish shows some kind of discoloration to the SS because of the heat but having seen that on most of the ones I've owned I suppose I can live with it because I keep it covered when not in use. I have a small tank which I tie-wrap to the railing and it works perfectly. I keep 1 or 2 of the small portable containers just in case I run out with the main tank but it has not happened. I have had to clean the holes of the burner when the flame started to lessen and to be blown out when windy, but other than that it has worked flawlessy. See Pic of installation.
The only BBQ I've seen that has worked perfectly and remained just as nice as when new is on a friend's boat. It's a smal Napoleon that he paid over 850$ for. Don't think they still make it but for me it's a moot point since I have no intention of ever paying that much for a boat BBQ.