RY4 from Dekang has always been my favorite, sweet and smooth caramel flavor, it's all I've smoked for over a year.  Now that Dekang has changed their recipe, it's now the worst flavor I've ever tasted.  Health Cabin's RY4 is decent, but still a different flavor.  If anyone knows of something comparable to Dekangs original, please let me know.  I'm down to my last few drops!