Weird - I could have sworn I went to their website last night, and this morning it's saying "no website at this address" !

Yes, I believe a big difference between Trios and Trios II is that the second design moved split the unit so that instead of being all in one box located in a drive bay, only the faceplate is there and the guts install in PCI slot (but not connecting to the slot). In some of the reveiws of the Trios, they complained that it was hard to connect all the IDE cables to the back, so maybe they switched the connectors to the PCI area to make this easier.

Find some more info on Trios II here

One thing I'd change in the design is not to have the switches exposed. Switching drives is not something you're going to do on the fly. So I'd take a little more precaution to make sure it doesn't happen accidentally.