Pre-requisites for BIA Implementation

Dear Experts,

Heres the situation ;

We just finished upgrading (TECHNICAL)from BW3.5 to BI 7.0.

The upgrade was a Non-Unicode type, although the vanilla system (BW 3.5) was unicode enabled.

Now, Before we implement BIA , is it necessary to go in for a FUNCTIONAL UPGRADE too??? If at all we do it, will it ,in anyway boost the performance of the system??

If we do not do it (i.e, a FUNCTIONAL UPGRADE before BIA), is there anything that we are loosing??

Additional Info : WE DONOT HAVE A SAP PORTAL.

Please advise..!!

Thank you,

Regards,

Sai.