Not on boats but I used this company for all those hoses on my TR6's engine and they were very helpful. As a rule silicone is easier to fit as it's more pliable, suitable for higher temperatures and less prone to perishing. It does, however, scratch easily so you need to be careful were it touches any other component and make sure a tywrap securing one hose isn't rubbing against another.
Thanks. The silicone Vs rubber was my next question, although with a heat gun I don't have too many problems fitting them, which is normally my biggest issue. These hoses are quite exposed, if not from vibrations from the engine itself then from me climbing around it frequently.