A great classic - leave Vienna on early Friday afternoon and reach the Prielschutzhaus, on Saturday reach the Grosser Priel through the Bert-Rinesch-Steig (C/D), on Sunday reach the Spitzmauer via the Stodertaler Steig (B, short) and go back home.
According to Bergsteigen.com, the Bert-Rinesch-Steig is "long (3.5h / 670m), steep and difficult, and is one of the biggest and most challenging Via Ferratas of the Alps". It's a great classic. When it was built in 1994 and at that time it was told "the last great ferrata in the East Alps which needed to be built" :-)
The Stodertaler Steig is just a short shortcut (45m / 200m) making hike on the Spitzmauer more enjoyable.
There is an option to use the hut's lift to transport backpacks up/down.
You can find photos here, here & here.
Please be aware that this trip is only suitable for people having dome experinece in Via Ferratas and fit enough for this long climb!