Several templates into same ERP

Hello ,

if you have 2 divisions : Division A running chemical business and Division B running oil and gas.

Both of them are planning a green field approach to SAP S/4Hana and want to limit customisation.

Would you deploy both templates into the same infrastructures ? what would be pros and cons ?

Would you deploy them into independent infrastructures ? What would be pros and cons ?

thanks for your inputs , we have some elements (infra cost, maintenance , service breaks ...) but I would like to hear from You , in order to avoid missing key points.

Edouard