The enclosure of the castle's thick of about 1 mm, not brittle plastic. The number mechanism is made of plastic. So that it is sufficiently stable. Perfect would be an approximately 2 mm thick fully rubberized housing, so it leaves no scratch marks on smooth surfaces and a more robust mechanism number of metal.
Since the castle, etc. No screws has to open it, it probably needs to be disposed of at a defect.
Against unobserved attacks the castle offers no major hurdle. The plastic casing could shatter with a medium-sized hammer and snap the steel cable with a 20-30 cm long bolt cutters.
The M-Wave model is apparently identical to a model of ABUS, but a little cheaper.
I bought this cable lock to secure several backpacks at the beach, you will not have to leave a guard on the beach ... :-)