The Steam train was only used to shunt the carriages into place in Coonor station, otherwise it's a diesel. Sitting on the left side of the train may give some better views but that is debatable. From other travellers who had done the whole journey from Mettupalayam to Ooty then the Mettupalayam to Coonor section may be a bit more exiting. It is nowhere near as much fun as the Shimla toy train.
If you own or manage Heritage Train, register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.