[OzStriker]

In my opinion the Great Ocean Road is a waste of time in terms of driving but a great sightseeing route. The high police presence, many tourists and frequent turnoffs and sightseeing points enroute make it unsafe and often a pain.

Mt Dandenong I consider unsafe for "driving" as well, many people live beside that that road, it is full of driveways.

I think you found the best road I can think of near Melbourne G.R, either clockwise or anticlockwise Healesville - Black Spur - Marysville - Reefton Spur - Warburton is a winner, with a turnoff at Lake Mountain for a run up and down during the non-winter months.

The highlight of the above roads would be Lake Mountain (but beware of the newer tarmac for the last 5 minutes on hot days) and Reefton Spur, where you will often have half an hour to yourself, 2nd, 3rd and 4th gear with not a car in sight.

The Black Spur was great with the 100 speed limit but with the 80 limit that has been there for probably a couple of years now, coupled with the high police presence, I find myself more worried about the speedo than enjoying the road...Those first few turns after Healesville though are probably the greatest bends in existence and in a well balanced car like the M3 will bring a smile to anyone's face!