For relational database, I would generally go for VMs that are optimized for memory such as:
Esv3, Ev3, Easv4, Eav4, Ev4, Esv4, Edv4, Edsv4, Mv2, M, DSv2, Dv2
For which Azure Region do you need that VMs?
Are you sure that most (~80%) of the CPU and memory will be used?
Do you know that you can also change the VM family or size at any time without any migration?
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Regards,
Didier