Interesting. On my 47 I use extreme regular size. Thought the lighter the better for extended heights for better control and handling.
Is the heavier wider brush really better? Am I missing something?
Generally speaking I would agree that using the lightest possible brush at heights is the best option. Brushes such as the Xtreme & Xtreme 35cm are really good on longer poles & would be my choice up to about 55ft.
However the question was regarding working at above 60ft with a 70ft pole.
At these top end heights we have found that many clients are not so worried about exact weight but rather control on the glass becomes more important. The extra width allows for greater stability on the buildings surface and reduces the effort needed to keep the brush head against the glass.
At 60-70ft it is rare for poles to be walked around with for much distance. Most time is spent with the brush head on the glass or resting against the building.
The Ultimate pole which is our only fully telescopic pole at above 64ft is not our lightest pole in any case - at these heights strength & control are as important as the exact weight of pole.
Of course the exact brush choice of each worker at 60ft+ will vary depending on working method & the exact nature of the building being cleaned. I do know of some of our clients who use a 45cm brush at these heights with the Ultimate pole as they prefer even more stability & greater glass coverage.