I have a stamina battery and it's nice, except I started having issues where the psp would just instant off. My theory was that the battery was so heavy it was pulling away from the contacts when I gave it the wrong kind of jostle--like setting it down on the desk. So, watch that. I went back to the original for a while but went back to stamina when I got Persona 1. Haven't had that problem re-occur so maybe it was just not seated correctly.