DEB powerwash concentrate is very good too, the beauty of the concentrates is the fact you can adjust them to suit.
I've used DEB stuff in it's diluted form to clean a cylinder head and pistons, left it overnight and it came out like brand new, all the carbon/oil gone
I guess it depends on what you are cleaning, I have a friend who uses some stuff through a foam lance to clean his pig units. He said he foams everything up and goes for a coffee, it gets everything off by the time it's rinsed, he buys 1000s litres of the stuff but I think it may be too agressive for normal use.
I’ve found all the products from this company to be good value and effective. Used to buy their tfr concentrate in 205 litre drums and dilute according to the job. http://www.espuma.co.uk/21.html