I am addicted to slushies at Sonic! I started talking about the first Sonic opening in my area a couple of weeks ago, and I love it. I like going during happy hour because you can get these slushies for half off between 2-4 pm every day.
I like the real fruit strawberry slushies and the apple juice slushies the best. Coming in a close third would be the regular cherry slushies. I like getting the really big route 44 size which is a 44 ounce drink.
I recommend finding a Sonic just to try their slushies if that is your kind of thing!