I've also just started using the Autobrite snow foam lance and Magifoam (with a Nilfisk c120). The thickness of the foam is excellent, but it doesn't remove that much dirt if you haven't washed the car for a while, but as long as it reduces the likelihood of scratches and swirls I'll keep using it. To me it doesn't really add much faffing, once the pressure washer etc is out anyway, the time taken to fill the bottle and foam the car is next to nothing and you can crack on with the alloys/filling your wash buckets while it's dwelling.
I think I'll try Tim's snow foam next.