My 18m high Spiderpole broke earlier this Summer in a thunderstorm gust. I have now replaced it with a new 26m Spiderpole with top three sections taken off giving total height a bit above 20 meters. I renewed guying using the guying belts which came with the pole. The old 18m pole was too flexible for "near" permanet use in my environment. Shortened 26m pole is remarkably stronger and more stable even in high winds.
The new pole got it's first challenge just one day after I got it up. On Sunday the 8th August, by the end of a very nice sunny day, we got a huge thunderstorm in Helsinki area with winds reaching 30 m/s. I have to admit getting a bit nervous when I saw the sky turning dark and the almost black storm cloud front approahing like an enormous tsunami wave in the air - and coming over us extremely fast. With the front came fast streaming gusts. But the antenna survived. The only thing needed was checking the guy lines a couple of times during the storm.
The storm toppled lots of trees and caused blackouts for more than 70000 households in Southern Finland.This is a link taken at a beach in Helsinki when the storm came: http://www.youtube.com/watch?v=KzGk_NXlobQ