IPHONE 3GS 8GB FOR SWAP ?

IPHONE GOOD COND ON O2 NOT SURE IF UNLOCKED ..BOXED ...WOULD SWAP FOR GALAXY ACE AND CASH MY WAY, MUST BE BOXED AND GOOD AND O2 ..AM, IN COLERAINE SO TO ME OR COULD MEET IF NOT FAR AWAY TEXTS OR CALLS ONLY NO OTHER SWAPS THANKS