blackberry torch 9860 o2 network £200 ono or iphone 4 ?

Hi im selling my blackberry torch 9860 its on o2 and only 6 months old i changed to it from an iphone 3 but just dont like it so trying to sell it and put the money towards an iphone 4. it comes with the box manuals and all cables as the charging cable doubles up as the usb for the computer.