Three models for nucleon-antinucleon annihilation are considered: the Fermi statistical model, the modification by Pomeranchuk which includes strong π-π interactions, and the Koba-Takeda model of fast “core“ annihilation followed by slow emission of ”cloud” pions. The parameters of the models are chosen to fit the experimental pion multiplicity <nπ>=5.36. Then it is shown that the Koba-Takeda model with a small core predicts quite different values then the other models for the average K meson energy and pion multiplicity associated with KK events. Data on these quantities would distinguish between models and provide indirect information on the π-π interaction.