Travelled on 29-06-2019 from MS to MDU in C7 (3-seater on track side)
Short Review: Amazing train. Average food. Speedy run feast by RPM WAP-7. On-time performance.
Deep Review:
1. Cleanliness: Super clean train. Coaches are cleaned after passengers have breakfast. Fresheners are sprinkled. Toilets are shiny and not stinky
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Punctuality: This train enjoys top priority in this route. Mostly before time at TPJ, Slightly late at KQN. Again on-time at MDU.
3. Food: Food is optional in this train. You can opt-out while booking your ticket. Food is very much average according to IR standards.
Around 6:30 AM, Biscuit and Tea/Coffee is served. Coffee is readymix.
Around 7:40 AM, Breakfast is served. 2 slices of bread and butter, 2 Idli and 2 Vada, Sambar and chutney, Muffin, Juice and Coffee/Tea.
No Lunch. Food is optional in this train. You can opt out while booking ticket.
4. Ticket Availability: Large number of seats available. No dynamic pricing.
5. Railfanning: Automatic doors, so no doorplating. Clear windows. Some toilets might have open windows.
6. Safety: Top class LHB coaches. Just 2 stops, so no intruders.
7. Comfort: Very comfortable seats. Reclining seats.
8. In-seat entertainment system took around a minute or two to start. GPS did not work. You will need to carry earphones/headphones. Hardly anyone uses them.
9. Toilets have plane-like vacuum flush system. DO NOT SIT and FLUSH. The suction is very powerful.
10. Coaches and cabins have automatic doors. While the cabin doors are sensor based, but coach door is not. Be sure to arrive/ board the train at least 5 minutes before departure.
11. Each bay of seats has 2 charging points. (For OnePlus users some points may not fit)
Pic 1: Coffee
Pic 2: Veg Breakfast

This below catering Menu is only for 22672 MDU - MS Tejas express...22671 MS MDU Tejas express catering menu is different..!!
I was onboard Tejas express to chennai on 19/04/19..!!
1. Rail neer bottle
2. Snacks Hot samosa with tomato ketchup, barone chocolate, haldirams salted peanut (this might vary for each day), parle biscuit, Tea/Coffee. This snacks served as soon as train departs MDU...
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and after TPJ it is served for TPJ boarding peoples.
3. Hot Tomato soup with bread sticks served while the train crosses VRI station...
4. Dinner as shown in pic...Menu will be written on top see it...!!
5. Finally Ice cream...That's all...!!
The best part of food was Tomato soup....Spicy Hot tomato soup with breadsticks combo...!!