i use several brushes
radius sill brush(medium bristle) for most work
supalite flocked black brush(ideal for leaded,old wooden windows)
supalite mono (conny roof/fascia cleans)
ive also got a few non gardiner brushes.2 vikans,ones used for washing the van the other is a stiff sill brush for very dirty conny roofs.
i also have a brodex brush but it never gets used.