Some windows just don`t come good with the pole,i`ve given some 3 cleans upwards and they still don`t come good.If you go in with the H&S angle the odd run and mark will be overlooked,but on bad frames and flaky paint if you go in saying they`ll come up perfect madam you`ll make yourself look a fool.Stick with the PVC windows,some still oxodize but not to the extreme i find of the painted type windows,99% of the PVC windows i do with the pole come up spotless but i would say that percentage is no where near with the older type wooden windows.