Place of business?

Yes. 

You can use the virtual office for company registration, GST registration, etc.

Since the virtual office gives you a professional address it can be used for all your business correspondence and mails.

No.... as per Definition of place of business u/s 2(85) , the virtual office cannot be place of Business.
As per Rule 18 of CGST Act : mandates that Display of registration certificate and Goods and Services Tax Identification Number on the name board

hence in regard to above in GST virtual office cannot treated as place of business.

Yes I do agree with Pankaj ji.

There is a mandatory requirement in GST to Display Registration Certificate, GSTIN and the name board at the Registered Place of Business.

So, if you go for a Virtual office, you will not be able to comply the requirement of GST Act.

Therefore, as per my opinion, Virtual Office cannot be your Place of Business.

Thanks