I use this Hilton quite frequently and the shuttle bus is a bit patchy. During the evening, the frequency drops down to about one an hour (maybe 45 minutes) but I've found them missing one. The shuttle bus stop is miles away from the terminal buildings and now that winter is here, its a very long way out in the cold to find that the next bus should be around in 45 minutes (but probably much longer). A cab typically costs €12-15 and gets you into the hotel in 10 inutes (minus the wasted walk to the edge of the airport

By the way, the staff there are a mixed bag - some are rather good but there is one receptionist that is argumentative and rude to every person who steps in front of her. I always make sure I am in another line nowadays (she is Eastern European with spectacles if you want to do the same!)

Just for completeness, the steaks are poor in their restaurant, breakfast is quite good, the HH points never credit correctly but the room rates are usually quite reasonable