Maybe not the whole € 100 ...

positive:
- Thin (it is in fact less than 5 mm thin!)
- Magnetic (this gives the keyboard very easy / off putting to the laptop's Tablet)
(- Lit: for the frugal, never turn on the light when working;))
- You can use them as envelope
- If one folds back, it is automatically turned off - if you fold forward comes from the screen

negative:
- Price -> I would sell the keyboard for 60-80
- It's a little getting used to a "normal" keyboard to this

Conclusion:
Maybe a bit expensive, but on the whole I am satisfied with the purchase. :)