It found that the range of the vehicle was typically only about 10 miles (16 km) rather than the 20 miles (32 km) promised by Sinclair, and reported that the C5's battery ran flat after only 6.5 miles (10.5 km) on a cold day. The C5's running speed was more usually around 12.5 miles per hour (20.1 km/h) than the claimed 15 miles per hour (24 km/h), while its running costs compared unfavourably to that of a petrol-driven Honda PX50 moped. The stability, general roadworthiness, and especially the safety of the C5 were questioned, and the AA suggested that the High-Vis Mast should be included as part of the standard package.[72] It concluded: