I am in the process of determining which Mac Book Pro to buy and what options I want. My question is about the firewire bus. Is the FW400 and FW800 bus independent or does the speed/thru-put of a device on one the affect the speed/thru-put on the other? To give an example, I plan to use the MBP for recording and other audio tools. If I use the FW400 for audio interface and FW800 for external HDD, does the bus speed or traffic of one affect the other? I am not sure if I am asking my question well, but I appreciate any answer you can offer.