The way ive been checking for leaks is to connect everything up except the kegs,disconnect them, then turn the gas on and let it pressurise up.
Take note of the HP gauge then turn the cylender off and leave it.
See how much it drops over a period of time.
I get >5 days out of my micromatic (i wanted to drink some beer), but the crappy dual reg i bought lasted ove
rnight.
Tis verry true that the poor man pays twice!
Back on topic...
I have a 6kg KK cylinder and will be looking for another in the future, its a bugger that the 2.6 and 6kg only have ~$50 between them. Appart from size It seems pointless to go the 2.6kg >_>