Green lake to Wartook is pretty straight. Between Wartook and Zumsteins there are Kangaroo Hazards to keep an eye out for, especially an hour or two each side of dusk and dawn.
Zumsteins to Halls Gap (over the mountain) is great, with many twisties, and a number of places for overtaking opportunities. Watch out for Campervans around blind corners - is usual to see them coming over the line by a few feet.
If traveling after bush fires (such as the first half of 2014) be careful of lose gravel and debris (small rocks) on the road. Road surface patch work tends to be tar and then loose stones thrown over the top, otherwise the road surface is pretty good.
An alternative route is to turn down Siverbands falls road. Half way down there the road turns to one way almost to the bottom - but it is tighter.
Awesome road, starts off with straight bits to gas it, then becomes nice and twisty with many good turns.