ok guys thanks for all that , great advice and insight as usual
might just go for slx 22 like u suggested pure just to get me up and running
my round is still small enough and maybe wen i double its size this time next year i treat myself to an extreme 
It depends on loads of stuff mate.
I have seen a chap on a set of step ladders using an 18 ft pole to clean a 3rd story window. The time he loses and the extra strain on his arms and back must be unreal as it looked very awkward. He saw me watching, and said "wanna go??" So i had a go and it was fine. Not saying i would ever do it, but its an option.
Window cleaning is about time and lost time is lost money.
If you don't have a lot of work and have days off. Then a slightly slower pole which weighs a few more grams is hardly gonna be noticeable.
When you HAVE to do £30 an hour 6 days a week just to remotely even keep pace with your round. Then your business smarts will kick in and we wont even have this conversation. You will buy an extreme and share your advice with the next newcomer
