Question: how much iops do i need?
Answer: 10,000 IOPS on 70 TB storage systems makes just 0.15 IOPS per GB. Thus a typical VM with 20-40 GB disk will get just 3 to 6 IOPS. Dismal. 50-100 IOPS per VM can be a good target for VMs which will be usable, not lagging.