That "flexible rod" part is the real game changer, not the brush size. I switched over last spring and the difference on gutters and under the eaves is night and day. The old cane setup used to whip around and smack me in the face when I pulled it back down, every single time. Now I can angle the head around corners without climbing up there twice. Did my whole back fence line in maybe twenty minutes last weekend.

A guy I used to work with swore by a hair dryer on the old Beech 1900 brake temp sensors, which sounds silly until you watch a thermal fault show up in 30 seconds that a meter missed all afternoon. His trick was taping a shop towel over the part first so the heat spread slow and even instead of cooking one spot. I still keep a cheap Conair in my go bag next to the good meter.