Definitely a memorable, unique experience for somebody looking to do something original while in Oslo. Museum and ski simulator are very average, probably not worth the trip just to see those things, but the zipline experience down the ski jump is really cool.
Get there early before the big tour groups arrive -- we were lucky to get there ahead of the 11:00 opening (hours change later in the year so check before you go), and were there just in time so we could be the first off the tower. Staff was helpful and friendly and helped make our young daughter feel comfortable (she ziplined as well).
Again, a great experience - a bit pricey but very unique and worth doing at least once.
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