SAP Business Objects Explorer on top of SAP BW

Dear Experts,

My Requirement:

- Use BO Explorer on top of SAP BW ( no HANA, no BIA ). This is to provide the users a set of related data and they can analyse the way they want.

Question-1:

- What should be the BW data volume that I should keep in mind for BO Explorer to have good performance. My concern is primarily because we don't use BIA or HANA.

Question-2:

- Can BO Explorer directly connect to a BW Infocube/Multiprovider or it has to connect only through Universes

Regards.