I still don't see how they are a pain. I live in a a relatively medium sized town. Both hyvee grocery stores, about 5-8 minutes apart, carry the refills for $15.00. I buy these 2-3 times a year. We also have two walmart stores in this town, both of which carry the cartridges. We also have a bed bath and beyond which carries the cartridges. I'm sure dillons grocery stores probably carry them also, and we have 4 of those stores. All of these businesses are within a 10-20 minute drive anywhere in town.
As for wretched flavors, this occurs with "normal" soda also. i don't see how people can drink half of the soda that is bottled and stored on the shelves, but to each their own. Try the diet orange. It'll make you pucker.
Yah. but if you are buying $15 per cartridge (at stores that do the trade in or it's more), $8 for a syrup bottle, and get about 20 bottles filled which are a liter each per bottle... it's not really cost effective.
1 liter = a little over 28 ounces. So 2.5 cans of soda per bottle. 20 bottles is 50 cans of soda. So it's about $23 for 50 "cans" of soda through the soda stream if you want fully carbonated drinks that equal retail drinks. Of course you can stretch the carbonation with less carbonation used per bottle and less syrup, but I'm trying to do an apples to apples comparison as close as possible.
50 "cans" of soda for $23. That is 46 cents a can.
Or I can buy a 12 pack of an off brand on sale for $2 each or $3 for a normal brand of soda on sale. That's 17 cents a can for an off brand or 25 cents for a normal brand. Hell, lets not use sale prices, so $3 for off brand soda or $4 for normal brand. That's 25 cents and 33 cents per can respectively.
So you are still talking a massive saving buying 12 packs at NORMAL prices than making your own soda stream. That doesn't even include the initial investment. Unless you get the syrup on sale, and make relatively flat sodas, you aren't going to be saving any money on soda stream sodas.
You can make it more economical by going to a paintball place. Last place re-filled my CO2 cartridges for about $4. In which case that is much cheaper to do if you have a paintball place nearby that is willing to refill them. Not everyone has that though.
Again that is assuming the $15 trade in price for spare cartridges. If not, you are buying a new one for $50 or so on average. Which is pretty expensive for a small little CO2 tank. Hell, comparable CO2 tanks for tippman paintball guns are cheaper than that.