I'm about to buy a 3g iphone, and had a quick question. I am not available for an upgrade because i signed a new 2 year contract in march. Instead of paying $399 for a 8gb at the non-upgradable cost, couldn't i save 25 bucks by paying the $175 ETF and then buying an 8gb for 199 dollars? Would that mean i would loose my phone number though? thanks for the help!