The new Imacs 21" also use a TI chipset, I will se the 27" ones in a few days. But to be frank the LSI chipset really seems to deliver good performence either with Lindy cable (rev. 6) or without (rev. 7).
When I compared my rev. 6 onboard Firewire with a TI based FW400 ExpressCard the card used about 2-5% more CPU. Unfortunately I missed to compare lowest possible buffer settings back then. But like all ExpressCards the whole thing was a bit flackey and would freeze sometimes when removing the card.
Concerning the repeater hub thing. If the Lindy cable with the inbuild repeater does not work then there's something wrong going on. Maybe the cable is broken or something. You can also try a HD drive, but with my Oxford based cases I found that only the FW800 port worked as bridge while the FW400 port still needed the Lindy cable in front in order to make the Fireface work.
One connection that worked as well was connecting the FF400 to a Motu Ultralite (as repeater). The Motu didn't even have to be turned on.