You have two routes from Saalfelden to Bischofshofen. The first, via Schwarzach is the main road. Very heavy traffic but well-kept surface and mostly fast sweepers. Use this only if you really have to, because the northern option - via the Dienten Sattel (1357m) is definitely the best bet and one of, if not the best, road around here. It's been more-or-less re-surfaced from end to end, with just a few yards of unevenness, and widened in a few places. Because it runs the same route as the main road B311/B159 it only really has a few touring campers on it. And bikes.

The road can be broken down into 3 main setions:

Bischofshofen - Mühlbach:
Excellent. the road runs trough a narrow gorge along a small river. The surface here is superb. It's about 9km and an absolute blinder of a stretch. I'd rate this section among my favourite bits, very similar to the Grein road near Linz and the Gorge d'l'Arly near Albertville. The first 2km through the gorge has been recently resurfaced and repaired. Only a little patchiogn and overbanding, nothing to worry about.
Mühlbach - Maria Alm:
A mixture of medium radius sweepers with real twisies with one or two easy hairpins. The scenery is thick woodland and alpine meadows ("The hills are alive...") with towering vertical mountainsides in the distance.
Maria Alm - Saalfelden:
Sweepers and straights. Lined with villages and holds no real surprises, not terribly exciting

This route also has the advantage of avoiding most of Bischofshofen, which is always a Good Thing.
Don't be put off by thinking the main road will be faster - I did the 46km (I admit I wasn't hanging around though) in 33 minutes, including stopping for a few piccies.

To make the best of this road, you should ride the Bischofshofen end, then turn left at Dienten and take the road down to Eschenau on the B311. It's twisty but a bit bumpy in patches - not enough to ruin the fun. If you're coming to or from the Grossglockner then this is the route to take.
[Closed between December and May]