Actually, I'm just now in the market for a system. Is that link to the same supplier you used? I'm on their page and they're showing a system with the Dell and one with the old T30. Which did you get and are you happy with it so far.
If I knew whether or not 7.4 for work for the 2005 model I have I would go down to Denver today and pick up a 7.4 multiplexer/cable set that a guy has here, but I don't want to waste time and $$ if that doesn't work.