Anybody used this device?

http://www.putzmeister.de/pm_online/data/BP_3245_GB.pdf

I have used one off and on for several years. They attach to a Putzmeister hose, which is very pricey. They do control the mud somewhat, but wear out fast. The hose that it attaches to would probably be considered a double ended hose, since the pour pin attaches to a metal end. I haven't used it much lately. For the price and the amount of control it gives, I wouldn't recommend them.

Does not work in practice, slurry leaks from top of the nozzle when 5 inch fills up. Heavy as to push around, rubber is hardly flexible. Would much rather invest in a 5" to 4" inch PM reduction hose.