Bergisel is definitely worth a visit and I would love to go there and watch some actual ski jumping. The architecture is stunning and the trip to the top is very good. The actual view from the top is stunning and you begin to get an idea how daunting it must be to do the ski jump. It was a bit windy but the kids enjoyed running around at the very top.
A friend told me that you can get a good deal on breakfast which gives you full access to the platform for a good price. Might try that next time