I would certainly recommend the trip, but I would break it up, with a stop in Adelaide along the way. You can have a break of either three or four days in Adelaide, with the westbound I-P transitting Adelaide on Sundays and Thursdays, in the late afternoon/evening.

Adelaide is a useful base for some sightseeing, with trips to the Barossa Valley wineries being worthwhile, as well as a stack of other attractions.Timing it so that you arrive on the Thursday afternoon and leave on the Sunday night would probably be the best way of doing it.

As for the train trip itself, I love it - I don't get bored, and the scenery is constantly changing. A lot of the time is spent in the lounge car socialising anyway, and it is a great way of passing the time. Trust me, you will love the trip.

Dave