Is it possible at the installation/config time to use of custom PC User instead of IUSR_METRO ?
There is a way we can do it, so you can use the desired user account instead of the IUSR_Metro, that is created on the Configuration stage, after the PC Server installation.
It will require to modify the username on the PCS.config file on the dat folder at the PC installation folder, previous to run the Configuration Wizard.
However this will require to open a ticket as we also need to encrypt the password using a workaround provided by R&D .
For more details, refer to the Performance Center Administrator Guide - http://support.openview.hp.com/selfsolve/document/KM00425856
Section "How to Change the System User" page 458