Stayed a weekend at Hilton.
Very nice and helpfull staff. Wonderful breakfast and location is perfect.
The hotel is very close everything but still in a quiet street (no noise from the outside) and has a subway just around the corner. The subway system in Vienna is fantastic btw.
Only minus is no free WiFi, but a lot of places (restaurants/pubs) has free WiFi around in Vienna so it was no big problem for us.
- Free Wifi