I don't use mine every day, it's really only for stand alone jobs and I don't have many.
Like Tosh, I found that by increasing the flow I can work faster, and in most cases not use any more water over the day.
I say most cases because you can't really work much faster if your doing three floor jobs, not with my alloy pole anyway, But you can really fly on ground floor work using a short[3ft] pole, and that 3 ft pole is superb when doing conservatories where the space is limited. Some conservatory sides being only a couple of feet from a fence or wall.
I have now increased the flow on my main trolley system with the same affect. I finished at 3.45 today where I used to have to work till 5pm. I carry 10x 25 litre containers on the van, and I usually come back with two having worked all day on a compact round. I now do the work an hour quicker for the cost of about 30 litres of water over the day. I wish I had done it a lot sooner. Dai