need some help with a hd external enclosure for a mac pro, there are so many to choose! and dont know anything about any of these brands. having a fan is really helpful? I really dont know how to choose, am looking for recommendations I'm searching for something that has esata and either firewire or usb or both (is firewire substantially better than usb?) these are some I found and think might be good Macally Vantec Thermaltake Rosewill Bytech Thanks in advance JJ edit: am about to order and would really appreciate any advice, thanks in advance!