LaCasera cream soda contains Aspartame and Acesulfame K with the caption 'Zero calories sugar free'. Aspartame has been linked with different side effects which includes migranes, vision problems, anxiety attacks, sleep problems while Acesulfame has been linked to bosom and brain tumors. This drink might be sugar free but it can also be sweet poison. Lets be careful of what goes into our body.
You can google these artificial sweetners for more info or check the sites below

http://aspartame.mercola.com/
http://www.sweetpoison.com/aspartame-sweeteners.html