FlexRay is considered the next generation state-of-theart technology for in-car networks, while time-triggered Ethernet emerges with the promise to integrate real-time and best-effort traffic into one homogeneous backbone. This paper contributes a competitive analysis of FlexRay and time-triggered Ethernet. By showing that it is possible to transfer a fully utilized FlexRay system, to a system based on time-triggered Ethernet, it is demonstrated that time-triggered Ethernet is a suitable replacement of current in-vehicle bus-systems. Further it is shown that a switched system has advantages in bandwidth utilization over a shared bus, when using group communication.