Never used a Glass fibre 18' pole but have picked one up and I instantly noticed the extra wieght. The trick. I find , is to use a nice light brush. I use "Tesco" Melody brushes.
The cones are twisters so not as easy as the clamps on Glass fibre poles. About every 3-4 months you need to replace the clamp inserts ata cost of a few quid.
I personaly wouldn't consider spending £100 or so on a glass fibre pole when I am quite happy with making my one "Unger" style Cleantech for about £60 -£70 all in, including a flow valve.
David