we are always here to help out foreign tourists in accordance to the indian motto : "athithi devo bhava" meaning guest is equal to god. firstly, there wont be any showers in any indian railway coaches. secondly, wearing nightclothes to bed is ok in ac 1st class as u have a lot of privacy there compared to other classes. comfort wise, AC 1st class is the best that's available. u will have privacy and also enjoy better services by the staff.