RaspberryPi 2 and B+ Case with magnets

My new version of the RaspberryPi Case with magnets. This is an improved design from my A+ case http://www.thingiverse.com/thing:580757
The RPi is held in with 2.5mm screws in the bottom shell. The screws are directly bolted into the plastic. I usually make sure that the holes fit the thread by drilling it with a 2.2 mm drill.
The top attaches to the bottom by 4 magnets. With that I am able to achieve that there is not a single screw, fastener, etc. on the outside of the case.

The magnets are 4mm in diameter and 4mm in height. I purchased mine from supermagnete.de with part number S-04-04-N