Kununu's default search for the current top companies based on predefined criteria is quite limited. Sorting by a descending Kununu score shows mostly companies with only a few reviews. These reviews are probably not representative and artificially boost a company's score. Furthermore, the number of reviews is correlated with the size of the company. Therefore it is quite difficult to scout for mid-sized companies with a high score. This tool fetches Kununu's Top Companies using their RESTful JSON API and provides an advanced filter and sort method.
Check it out at roberthree.github.io/kununu-advanced-filter.