D2-D3 Switcher is a simple PSP homebrew to switch easily from CF 5.50GEN-D3 to -D2 and viceversa. It works changing only the peagasus.prx in Flash0. Returning to D2 (using the D2's peagasus.prx) you will can use those savedatas that appear corrupted in D3 or play those games that have issues with D3 (such as Jak and Daxter, Metal Gear Solid Peace Walker, etc...). But remember to come back to D3 when you want to play those modern games that require it.