Distribution network operators require more advanced planning tools to deal with the challenges of future network planning. An appropriate planning and optimization tool can identify which option for network extension should be selected from available alternatives. However, the evaluation part in these optimization approaches results in many power flow calculations, especially in case of networks which need evaluation of reconfigurability capacity. An iterative approach like the generally accepted AC power flow is a relatively computational expensive evaluation method. Therefore, it is investigated if a linear power flow method with line outage distribution factors (LODFs) can be applied. This paper identifies the trade-off in speed and accuracy of LODFs regarding the evaluation of reconfigurable medium voltage distribution networks.Index Terms--Distribution network operator, line outage distribution factors, medium voltage networks, power distribution network planning, AC power flow, DC power flow.