Several studies have been made on comparison between synchronous and asynchronous NoCs (Network-on-Chips). However, very few attempts have been made at fair comparison between synchronous NoCs designed by synchronous researchers and asynchronous ones designed by asynchronous researchers under the same functional specification using the same fabrication technology. In this paper, representative routers of both design styles are individually designed under the same conditions. Then, they are precisely compared in the viewpoint of area, latency, power, and fairness. As a result, we show "areas of specialty" of both routers, e.g., real-time control systems for asynchronous routers and multi-media data processing systems for synchronous ones.