Home made soda

For this Christmas my DH asked me for a Soda Stream that would allow him to make his own soda. He loves his soda and can drink quite a bit of it every day, but it's also expensive and from what I've seen in past year prices will only continue to rise. In the past I could stock up with soda when it was 5 cases for $10 but this is just a dream now. Normal price for 12 pack is $4.95 and when its on sale it's 4 for $12 which is not that much better. Buying large 2 litter soda bottles is alternative except for the whole using plastic that I'm not a big fan off (aluminum cans at least can be recycled and reused while plastic not always makes it back into the reuse even when we do recycle it). So we got soda stream and so far I like it mostly because I control what I put inside - sugar or syrup or premade mixes. Honey likes his sweet and I not so much so I can make mine with just a little of sugar syrup or with maple syrup or a fruit juice. Technically what we make is a fizz watter - seltzer - using regular water, CO2 and a flavoring. I like with homemade ginger syrup - which also makes candied ginger as result which I can use in cookies.

So the most obvious question would be - is it worth it. Let's do a bit of math.

Soda stream original price = $130 makes 130 liters of soda because it comes with full bottle of carbonator equals to 65 2-litter bottles in store. So not exactly less expensive on first pass.

Next carbonator refill pack comes with 2 bottles that can make 130 liters each so that's 260 liters for about $50. If you buy it in BedBathandBeyond then you an use 20% coupon to lower price.
This would equal to 130 2-liter bottles soda in stores on one refill. Definitely price saver. I guess it eventually equals out if you add original price and then will be savings afterwards.

And what's more important in my view - no chemicals :)