I just purchased a 27" 3.4 iMac and I want to upgrade the stock RAM. I'll be using the iMac for video editing in FCP and encoding in Compressor, occasionally running them simultaneously. Currently I'm deciding between buying OWC's 8GB (adding it to the stock 4GB) and 16GB RAM. Will my computer notice the rendering and/or multitasking performance boost with 16GB Ram over 12GB? Or should I just stick with the cheaper option.