Sinclair C5 major consumer organisations published sceptical evaluations. The Automobile Association questioned many of Sinclair's claims in a report published at the start of May. It found that the range of the vehicle was typically only about 10 miles (16 km) rather than the promised by Sinclair, and reported that the C5's battery ran flat after only on a cold day. The C5's running speed was more usually around than the claimed , 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
Sinclair Executive consumption, creating issues with the reliability. The Executive Memory was launched in November 1973, with the same physical dimensions as the original, but with the ability to memorise subtotals from any number of chain calculations. There were at least 3 versions, including the black and white Type 1, and the Type 2 with a gold keyboard. The Executive Memory sold at the lower price of . Sinclair Executive The Sinclair Executive was the world's first "slimline" pocket calculator, and the first to be produced by Clive Sinclair's company Sinclair Radionics. Introduced in 1972, there were at least two different versions