IME flying to/from MEL was always the issue with priority.
SYD T1 and non-MEL flights T3 my bags seemed to come out near the front.
MEL I have experienced long waits both international and domestic, in fact I really am not that big a fan of MEL (the airport, the city is a wonderful place to visit).
However I must admit I have generally stopped caring or counting as that could of course increase my agrivation levels about travelling. I just let it go as life is too short to let these minor things get to you....unless of course bags not coming out after 45 minutes, needing to transfer to a different terminal to check in for an international flight, that only departs 3 times a week....I am talking abut you IB and MAD