Performance evaluation in terms of energy conservation and data reliability of the IEEE 802.15.4 multi-hop communications in error-prone Wireless Sensor Networks (WSNs) is an emerging research issue. In order to accurately evaluate the energy consumption of a sensor node and ultimately the lifetime of WSNs, it is highly desired to thoroughly analyze data reliability through variety of aspects. In this paper, we analyze data reliability in the IEEE 802.15.4 multi-hop communications in error-prone WSNs, by assessing the channel quality using both physical and logical channel quality estimators with different set of parametric values of IEEE 802.15.4 Medium Access Control (MAC) protocol. On the basis of these estimators, we approximate the energy consumption of a sensor node. We also analyze the overheads caused by packet forwarding in the multihop WSNs. Simulation results indicate that although physical channel quality estimators are dependent on hardware characteristics, they show better performance in terms of energy consumption and successful data delivery compared to logical channel quality estimators.