Capture and Replay workload

We have a new server which we are migrating too and want to see the potential benefits of the hardware. So the idea is that we capture a workload and replay this against our new box. My question is however in regards to seeing the performance benefits. I will be running some perf counters but ideally we want to see how much quicker individual queries are. I will have this information in the initial workload capture, however when I replay this on my new server do I simultaneously need to run a trace to capture the new workload information also. In effect running SQL profiler twice at the same time for replaying and capturing?