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Traveled from CDG to DGR
Cleanliness: Top notch cleanliness. Even before it got refurbished the cleanliness was good. (In AC Coaches). Hence would rate it 4/5.
Food: Try avoiding the PC food. My personal experience, too much costly against what they are actually offering. Rather go for e-catering, because at same price would get better deal. Apart from that for snacks, breakfast etc it is good, but try avoiding for Lunch and Dinner.
Punctuality:...
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Quite a time take this train when could not get the Rajdhanis from New Delhi. Punctuality was worst for this train once. I personally have traveled both during winter and summer and my experience was really horrible. But recently everything has just changed to opposite. The punctuality of this train has increased to a lot. Now a much punctual train between Kalka and Howrah. But yes very unreliable during winter.
Security: Security is good. RPF, TTE and attendants are quite active. Once a off duty RPF sneaked inside the AC 3 coach by boasting as a Staff. The Attendant and the TTE forced him to sit outside and travel at the seat near the toilets.
Overall Experience: Good experience. Everything is good. If I have to choose in between Poorva and Kalka Mail, I would rather go for Kalka owing to its cleanliness and service. My personal opinion, different people have different opinion. But yes during winter quite unreliable, can even get late by more than 10 hours. So watch out for that during winters. Apart than that a very good train.