Thank you Kolbas for your interest in PiMP.
Yes, you can do /opt/pimp/atiflash -s 0 /root/gpu0-biosbackup.rom to save your existing vbios, and then flash other bios files, for example. Then a simple reboot is all that is needed. For more advanced changes, until we get a more advanced tool, you can still modify the VBIOS using windows tools for now.

We are working on getting some more guides on how to mod BIOS on the pimp workshop: If you would like to contribute please do