Help with downgrading

[JoeBoi]

Hi guys I wanna downgrade a PSP from 2.80 I got a update called 2.80Euro from another site and was wondering if its alright to use this as the 2.80 to downgrade from also with the 1.50 Firmware is it ok to use US version or does it not matter since there is no UK version just making sure as don't wanna brick it :D

[Shrygue]

It does not matter wheather the 1.50 updater is US or Japanesse as there isn't really a difference between them, either one can be used with the 2.80 downgrader.