This is definitely a very good and impressive museum, with full coverage of Ground Air Sea and Space vehicles of many kinds, some real, some are models.
There are also many activities and interactive attractions for children even of small age.
You can easily spend half a day there.
The only disadvantage for us was that it is not so friendly to English speaking visitors, and most of the interactive attractions are more suitable for local visitors.
Do not skip it if you are in Lucern.