As the changes of toolkit versions happened quite often in the last time, the need for Superbuilds emerged more often than it was convenient.
There are solutions for avoiding the SuperBuild dilemma (building MITK from scratch doesn't take that long):

1. pre-build the toolkits for different supported environments (e.g. VS 2017, GCC 7.3) and store them on the network-drive. The toolkits are updated on a regular basis and tested with the current master
2. use a package manager (e.g. https://github.com/Microsoft/vcpkg)