I really wouldn't change your PSP with yoru friends that is beat up from years ago... I would keep it man.. Running homebrew is great but having a USED PSP that was released in 2005 is not fun..
If I was you I would just keep my PSP and play my games andd wait until a downgrader is available . They'll come... They'll just need time to do so.
Dont exchange it with your friends.. DOn't give him a BRAND NEW PSP.. just to have Homebrew. Keep yours.
If you have the receipt and it was purchased recently exchange it at your store.. Try looking at the box

to see if the firmware is downgradable

by looking at the retail box. IF I was you try to find one box that says the "K". thats a 2.71 ... It was easy for me to downgrade it ..
To know that .. go to this thread. http://www.pspmod.com/forums/showthr...82+motherboard (4g memory)