It would be interesting to see the comparison with non-GC implementations of the same algorithms/benchmarks - for example in C...
But the bigger ones are not yet (so, no results yet).
One of the important questions to answer first is how the mapping should be done. A naive version using new/delete/smartpointers is going to have performance issues. Other options would be to use arena allocators and completely remove memory management overhead from the equation. Depending on what comparison/C++ usage scenario is desired, both options would be useful.