Ok this might be long but i got a couple of questions. I bought a used psp slim 2000 from gamestop and I was going to hack it but luckily me it was already. So right now the cfw for it is 5.00 m33-6 and I have the kingdom hearts umd from my friend but i cant play it because its telling me I have to upgrade to 6.20 or higher. I looked at the forums and found out about Prometheus-4 but is it only for iso's and UMDs or just iso's only? Now if I have to upgrade my cfw which one is the best one out there?