Knot, Gold River has always won out for me and I'm towing and launching a boat that's 10+ wide, 13'5" high and weighs over 15,000. If you plan the tides right Gold River is your best option versus all the miles over the gravel. I've never towed into Tahsis so I don't know the condition of that gravel road. I have towed the gravel to Zeballos but went very slow.
It all boils down to what your comfortable with.