Xylitol not only has far fewer calories than sugar, it also prevents insulin levels from rising. What's more, xylitol cares for teeth and "kills" caries bacteria, so you can actively do something to prevent tooth decay. It tastes very similar to granulated sugar.
Why are there still no drinks sweetened with xylitol in Migros? At least I don't know of a single xylitol drink from Migros. It would solve virtually all health problems in "one fell swoop" and the taste of the drinks would hardly change.

Please bring xylitol drinks! :-)