The Soda Stream Due is already the third system I use. If the first devices were functionally top, they seemed rather cheaply made. The current SodaStream Duo is high quality! It has a noble look. Handling is child's play. Just like inserting the new cylinders. I can't say yet how many bottles I can fill with it, because I usually want a lot of fizz, so I probably won't reach the number of litres. But for me it's all about not having to carry water and our tap water is top notch! I think this system will stay in our household ;-)