I'm just curious to know which 20" iMac you think is better: - Rev B 2.0GHz G5 processor with 2GB DDR RAM, or - Rev C 2.1GHz G5 processor with 1.5GB DDR2 RAM? Which would give better performance - the extra 512 RAM in the Rev B or the 0.1GHz processor difference in the later model with "faster" DDR2 RAM (even though there is only 1.5GB)? I'm not interested in Front Row or built-in iSight in the Rev C and I don't want to buy the Core Duo. What's important to me is the performance of the machine and also the noise-level. For those of you who have owned both machines, have you noticed any difference in performance? Also is the Rev C really quieter than the B?