Review of Sour Blue Raspberry Flavor-Cap:

Cap's Sour Blue Raspberry is a very good flavor-it isn't very sour though. But it's sweet and has a good blue razz flavor to it. It tastes like candy-which is what it should taste like! I used it at 4% and 5%, with WF sour 
blue razz and with LB blue rasp slush. It really helps both of those to become fuller blue rasp flavors.  Give it a shot!