I have been using Emergen-C for years now and have tried other flavors but have been coming back to orange as my favorite. It is easy and quick to take and taste good as well.
I will drink Emergen-C along with your classic immune boosters whenever I feel a sickness coming on -Good N' Natural Olive Leaf Extract + FREE Echinacea Goldenseal Drops (Alcohol Free - 1 oz.). I've been following this routine in recent years and for the most part, it keeps me from getting sick when it gets cold outside.
I know not everyone like the taste of the Emergen-C but for me personally, I love it, and if it can boost my immune system get my body some extra vitamin C, then I'm all for it.