I have to admit, back in the mid 90's when I discovered the Guava Lip Smacker in the Tropical Treasures six piece set, my flavor palate was unfamiliar with such exoticness and it felt so posh to have. I will never forget the flavor either, it was very fruity and a little sweet, not like any other Lip Smacker before it. My original has lost quite a bit of its flavor but I remember it vividly.
In 2010, Bonne Bell revived the fruity favorite, in original (alongside Pineapple and Coconut in a trio) and in a new 100% Natural Lip Smacker formula. The formula sported a very different flavor profile than its 1990's one- this had a little more of a sour appeal, but still very different than any other Lip Smacker that has come around. The 100% Natural formula was very light but still had a similar fruity and sour finish. Guava is now rare again, so if you come across it, it's definitely a collectors piece.