I don't have any idea about internal maintenance but coaches do look for the lack of better word outdated at least from outside.
Even exteriors of Long Distance trains can be maintained neatly, even Chennai is a coastal city but there's humongous level of difference in maintenance of this train and Tamil Nadu Express.
Haven't traveled yet so don't know but a few people I know have travelled and really aren't that impressed.
Regular...
more... travelers might enlighten on this issue.
PLEASE NOTE: No offence meant to Visakhapatnam Fans or Andhra Fans, I'm just saying about what we all are seeing.