Just what the (iMac) doctor ordered
One thing that bugged me about my 27" iMac was that there was just one Firewire800 port and I don't like daisy-chaining a lot of audio interfaces and hard drives (not to mention some are 800 ports and some are 400 ports). This little device allowed me to spread out the drives and audio I/O devices onto their own chains. I know it's still just one port/buss into the iMac but for my money and needs, this little guy did exactly what I wanted it to. No muss, no fuss.