for os9 clearly u would want one with a fw400 interface or a fw800->fw400 cable
i have one of these rocketfish 1394a -> 1394b converter things and they are clumsy + prone to falling out
diehard tels me the fw400>fw800 cable is the way to go to avoid the clumsy adapters
heres an example..see how long it is? i dont understand why they have to be so big
mines actually the reverse of this, with a male fw400 part and a female fw800 part because its for adapting my fw800 drive + fw800 cable to connect
to a fw400 port...
heres a pic. on the right
seems to me to be the best idea to get a fw800 enclosure that either has both fw400+ fw800
or also purchase the fw800->fw400 converter that way u have compatibility + the higher speeds
when using it with a fw800 capable mac (2006-2011 macs)