6.60 pro-c2

Hi all, I have a PSP 1000 phat with a working permanent 6.60 PRO-C2 CFW, I read about a "fix 3" version of my CFW wich should fix some old bug, I would ask you if it's worth the risk of a CFW change and if so, I can update directly old CFW to the new one or I've to restore an OFW and then back...