We analyze the performance of a reservoir computer based on time delayed feedback and optical injection, which is drawing benefits from the high-speed polarization dynamics of a Vertical Cavity Surface Emitting Laser (VCSEL). We demonstrate that such a system has high computation performance and yields deeper memory than existing single-mode laser-based reservoir computer. Performance is demonstrated on several benchmarking tasks. In particular, the error rate is an order of magnitude smaller when performing channel equalization.