I am in the market for a soda machine and/or pop machine. I drink diet cola and my wife drinks Perrier (though I may switch to straight soda). We're figuring it would be cost effective as well as more convenient to get our own machine - if they work. Does anyone have any experience or advice? Does anyone know where I might read some reviews of machines to determine which will suit our needs? My concerns are: 1] Is it cost-competitive? (doesn't have to be cheaper, as long as it's not outrageously more expensive) 2] Do they work? Do they actually carbonize the water? Is their carbonized water comparable to bottled carbonated bevys? Or do they go flat faster for some reason? P.S. as a Canadian, 'soda' and 'pop' are distinct things. 'Soda' specifically refers to soda water.