I have a 20" 2.16Ghz iMac/2GB RAM/250 HDD. It isn't under applecare. Someone has just offered me $650 for it (without keyboard/mouse). My thought is to sell it for $650 and put the money towards a $1299 refurbished MBP (2.4GHz/15"/9600M), and pay the rest of it off on a 12-month/no-interest finance. 1) Should I be asking for more for the iMac? 2) Should I just cross my fingers and hope the iMac lasts two more years without dying? What would it sell for in two years? Thanks.