Oh boy Dennis.. this will open a real can of worms here
I am going to give you MY experience... I speak for no-one else. Also as a supplier of WFP equipment I would be expected to say that its the dogs b*ll*x.
In the vast majority of cases.. if used properly WFP will.. after the first couple of cleans leave a better finish than trad. The main reason for this is that by using pure water only to clean you leave no residue on the surface for dust etc to stick to. There is a definate "sheen" to a window.. and that includes the frames that has been cleaned a few times CORRECTLY with WFP.
We use it on mainly domestic work.. a real mixture of it.. from small terraced places up to very large in own grounds etc. We still use trad and I cant ever see us not using it but all in all by changing to WFP our results are better and.. we are around 50% more productive.
Now.. over to the rest of the opinions and experiences.
Andrew