I think it represents decent value if you plan to visit at least 15 times. Only gets you half price at Verkehrshaus but that's 30CHF saving for a family of 4. Other ones we have visited in last 12 months and would recommend are; Landesmuseum Zurich, The glacier garden museum in Luzern by the lion monument (including a great mirror maze), Natural History museum Luzern, Military museum Bern, National museum Bern, Natural history Bern, Alpine museum Bern...... just off the top of my head, add to that the Paul Klee centre which I enjoyed with my daughter but my wife and son didn't

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I think you would get your money back just with above.