in a word.. no. been there done that... cancelled my diploma course and stopped at cert iv as it really was taking double the time...
at tafe you sit the exams but they arent recognised by casa and vice versa. So you have to resit them again anyway taking a day off tafe to do so.
the only advantage is if your a full time student then it can be free at tafe... and if your really really bad at study you get a whole year to do what should take you a month...
Most schools can offer it in conjunction with your flight training... so if your doing the flight training then a cert iv is basically a cpl, diploma is cpl with either instructor or instrument rating and generally add on the atpl subjects at some places...
just look for vetab approved training and shop around i guess...
goodluck.
