Feasibility - 13k employees Planning in WFP?

Hello Gurus

In EPM cloud, workforce module (OOB) is it feasible to do Employee only or Employee and Job level planning for present 13k permanent employees (keep into mind near 5 year future could be around 15k-17k). (leave apart the contractors - if we add contractors the present count is 25k employees)

I think Oracle's out of box product EPM cloud - Workforce will definitely have performance issues with such huge number of employees - and I would like to be challenged if I am incorrect on this assumption of mine. Would like an honest feedback based on your experience and what was done in this case please.