For me I found using a washer telescopic lance for fsg's a lot more hassle than it was worth. Not only that if the pressure/flow was too high could easily damage plastics, blow trim off, make joints leak, force water into the roof space etc. If attempting to clear blocked downspouts and clear out guttering could also blow the plastic swan necks apart. Not to mention can make a hell of a mess and blow end caps off too...Oops!
Now I prefer the wfp softwash route and spray bleach everywhere instead... Yehaa! ride em cowboy lol