Three demonstrators, 3M1-3, were purchased in 1981. They were 12 metres in length with one exit only. However, KMB chose Leyland and Dennis for more 12-metre buses only, and these 3 buses were the only 12-metre Super Metrobuses in the fleet.

During 1983-89, 88 Metrobuses with 2 axes and 9.7 metres long, joined the fleet. Some of them were specified for climbing hills, and were fitted with more powerful Cumminus engines and Voith DIWA 864G gearboxes.

S3M1-254 are the final variant of KMB Metrobuses introduced during 1986-90. They are 11-metre 3-axle buses. One of the buses, which was registered as DP 1932, had been fitted with Sutrak air-condition unit for experimental purpose. Finally the trial was judged to be a failure, and the air-condition equipment was removed. The bus was finally allocated a fleet number of S3M145.

For photographs of different classes of MCW Metrobuses in the KMB fleet, please click the relevant links for the pages below.