My PSP 100x has been on 5.00 M33-6 for quite a long time. It ran almost any ISO/CSO I threw at it. However in the guide it says I may update to 5.50 GEN-D Prom 4 or whatever. Is this really worth it? And now I'm seeing ISOs 'signed' for 6.xx, will I be unable to run these? I've been out of the scene for a while, help me out ?