 When introduced in 1917, the N class proved adept at hauling both passenger and freight services on the SECR.They were well liked by crews who appreciated the general robustness of the design, although the lightly built frames caused excessive vibration and rough riding on the footplate when worked hard.Despite there being little wrong with the original design, the N class’ full steaming potential was not realised because of the failure to capitalise upon a larger boiler, which was a direct consequence of Maunsell's standardisation policy.