Do you think that there will be Zcache benchmarks? Thats interesting. I know that IBM never releases Mainframe benchmarks, because IBM does not want people to know how slow the cpus actually are. For instance, you will never find any SPEC_INT benchmarks for Mainframes. Then you could compare a normal x86 cpu, vs a Mainframe, and you will see that the Mainframe is way slower.
This is unrelated to IBM. Also I think some are confusing zcache with zram, IIRC only zram is available in the CM rom. Zram on its own is very useful on low-ram systems though, I should know.