I have been using WFP since April, my income over that period has increased by around the 60% mark, and as I am (overall) much quicker than before WFP I am now about 30% below capacity.
It has increased to the point that I shall now start to worry about my tax bill for this period when it comes around next Xmas
Funny thing too, I now love the jobs I hated, those accounts with steep gardens, georgian or leaded windows, slippery patio's, difficult to reach dormers on on a steep roof, big 3 storey houses
.
But the small one or two bed semi's that you can whip around with your ladders in ten minutes have lost there attraction, they can't really be done any quicker
It does take a few months to really start to get the hang of it, and first time cleans can be hard work, and there will always be times when you are better off using traditional methods, there are not many days when I don't use my traditional gear at some point.
Upshot is; you will be considerably quicker and Immeasurably safer
Ian