I was a loyal Lab-X customer, but since they vanished(!!), I've been using Bond Imaging, near Richmond Railway Station, and they have been great - no problems, same price as everyone, friendly, lots of services, and fast - email me when a job is done. Also, they appear to be the only lab left in Melbourne still doing C41 processing for sheet film.
I've never had a problem with roll film processed at Vanbar in Carlton, either, but they are SLOW (three days for C41), and (minor point) I hate the way they tape up the rolls so tightly - makes the film really difficult to flatten for printing or scanning...

Bond Imaging