This thing is dead simple and works great. It requires no power source and has a pretty small footprint. I have never been much of a seltzer drinker, but now I pretty much exclusively drink highly carbonated, unflavored water.Funny thing is, I bought this for my significant other. She is a seltzer addict, and likes this just fine. She enjoys the serious concentration of bubbles you get with this. I did not expect to get in on the action, but here I am.I really have no issues with this, after a year. It makes really fizzy water, and the water stays fizzy for hours in the bottle with the cap closed. It takes seconds to make. Two two-second pushes of the button and you are good.Do yourself a favor, and buy a CO2 tank (like this - https://www.amazon.com/dp/B00IE1DJ2I) and get it refilled at a place that does home brewing, or a commercial beverage supplier. Look around online and see what's in your area, before buying a tank, of course, but if there is anything around, do it. You will save a lot of money versus doing the exchange on the little cartridge that comes with it. If you decided to go this route, the only other thing you need is an adapter (like this - https://www.amazon.com/dp/B0CP96GL76) to go between the cartridge and tank. Look for videos on YouTube. It might seem scary, but it's really no big deal, in my experience. The tank has already paid for itself, no question. I fill it for $20.Drinkmate will only let you send back at least two empty cartridges. This comes with one, which would mean you have to buy a second to send back and get a $20 "coupon" to use on buying more cartridges, which start at $60 for two (before "coupon") plus shipping and tax. It's not hard to figure out that buying your own tank is the way to go, if you can swing it.You should probably also buy more beverage bottles, unless you live alone or only one person will use it. Keep in mind they expire, so don't buy them just to buy. The expiration maybe seems dumb, but I do suppose that constant pressurizing takes a toll on the plastic.