If I buy an iphone from O2. (�269 bit high I know) Can I just get it unlocked and put my Vodafone sim card in it and it will work fine and my number will be the same?
When you buy the iPhone it is not activated and does not work at all until you activate through iTunes which involves signing up to the 18 month contract with o2. Only once you have done this does the iPhone come to life. You could then have it unlocked to work with another providers sim card but each time you sync with your iTunes, apple will lock it again. Pretty pointless doing it if you want to regularly sync to put new tunes on it!