Coaches would be clean. (You will have charging points in some coaches also, but not exactly sure which will have)
Since the pilgrim season (Sabarimala) is over, there wont be much intrusion of unreserved pax.
Lunch can be had at SC itself...Snacks can be had at Guntur, Dinner at Gudur is really good at PF 1 catering stall. Next day morning, breakfast can be had in Coimbatore Jn.
Train...
more... will run with some late till Guntur, sometimes till Nellore also..But will be on time to Erode and from there on maintains the time.
Washrooms are clean. Another cleaning would be done at Erode in the morning.