Had sodastream growing up and was always exciting when we made soft drink!! Anyway point of thread is!!

DH loves mineral water rather than still water as he likes the "scratchy" feeling of the bubbles!!! And he tells me this is why he drinks soft drink, I buy him sparkling mineral water but he drinks it so fast that its $$$ to keep buying SO I was thinking, for fathers day I would maybe buy a sodastream for him!!

BUT do you think this is cost effective?? How often do you replace cylinders? how many bottles does it FIZZ??

Thanks