In the last few years, several studies have analyzed the performance of flooding and random walks as querying mechanisms for unstructured wireless sensor networks. However, most of the work is theoretical in nature and while providing insights into the asymptotic behavior of these querying mechanisms, does not account for the non-idealities faced by the network in real deployments. In this paper, we present an empirical evaluation of the performance of both flooding and random walks in real environments. The metrics considered are delay, reliability and transmission cost. Our results suggest that flooding is better suited for low-interference environments, while random walks might be a better option in networks with high interference.