Epidemic spreading is a common approach to mitigate frequent link disruptions and to support content-centric information dissemination in opportunistic networks. Stochastic models, often used to characterize epidemic processes, introduce assumptions which, on one hand, make them analytically tractable, while on the other, ignore attested characteristics of human mobility. We investigate the fitness of a simple stochastic model for content dissemination by comparison with experimental results obtained from real-life mobility traces. We examine four mobility datasets and consider content delivery delay as a performance metric. Our finding is that a homogeneous model is unable to capture the performance of content dissemination with respect to content delivery delays.