It was a question, but I'm sure you knew that..
I can't do testing myself for a few reasons :
1.) MacBook Pro is dead (http://forums.cnet.com/7723-21565_102-561465/reviving-a-dead-early-2008-macbook-pro/)
2.) MacBook Air has no FireWire ports, and any adapters are extremely scarce and expensive
3.) I don't own the LaCie Thunderbolt drive (yet), and I am not going to purchase it, unless I can make sure that the performance will be at least the same or better. (That Thunderbolt drive is not cheap.. and I would need at least two)
Which is why I asked my question about these.
So, I was hoping that experts here can contribute something helpful. At least in theory, people here are better informed than me about how these things work I believe... While I know that Thunderbolt drives are not widespread as of yet, somebody might be familiar with the connection types and drive speeds.
Anyway, working with 2TB of media files on a daily basis connected by USB is a painful experience. So again, any suggestions would be highly appreciated!