I started using this product recently on both outside and inside windows, here's my review:
INSIDES I add 1 capful to 500ml bottle of pure water, prob a bit too much but what the heck. Solution goes on the glass with applicator as normal. Seems to do a good job of cutting through the dirt, but no better than other cleaners like Squeegee Off etc. Very little suds, which is a plus in my book. Very slippery on glass, very little pressure on squeegee required, which is great. Also stays wet for quite a while longer in direct sunlight. Leaves glass sparkling, prob more so than Squeegee Off. I think I read somewhere that this stuff eliminates the need to detail, but that wasn't my experience, however I don't dog-ear my channels so maybe it is possible.
OUTSIDES For the outsides, I add 3 capfuls to 5L of pure in my modified 5L sprayer. I then wfp this to all the glass and frames of each window of the house. I then wash all windows with just pure as normal. This obviously increases the time it takes to complete each house, but apparantly the solution contains microscopic cleaning molecules that adhere to the pores of the glass. These molecules become active each time the glass is wet, similar to self-cleaning glass, and so in theory the next time i go to clean these windows it should be much easier and quicker than normal. I've treated about 20 houses now, so i'll have to wait till they are done next time to see if it has made any difference. I will say that after treating the glass and then cleaning with pure, it was much easier and quicker, but that's prob just because glass had been pre-soaked, prob be the same if I had pre-soaked with water only.
In conclusion, I'm very happy with the results for inside cleans, and would definitely buy it on an on-going basis for insides alone. I'll have to wait and see how effective it is for the outsides, but I'm hopeful it will do as it claims. I couldn't find any informatiion on how often it has to be re-applied to outsides, i reckon it would need to last for around 10 to 15 washes to be worthwhile.