I've been thinking about upgrading from my 15" rMPB to the current 27" iMac. My reasoning is mainly because I need better performance for video editing and rendering. But I've noticed that the iMac with the i7 3770 CPU only scores about 400 points more in Geekbench than the rMPB. Does this mean I'm not really going to see any performance difference between the two? I'm starting to think a Mac Pro or custom built Windows machine might be better options for maximum performance. Thanks for any info!