Thanks for the opinions so far.
I agree that the '05 silver is probably not worth $11,500 so would have to negotiate to a better price.
Depending on how the test drive and viewing goes tomorrow, I may end up looking at the '06 black on black. I think I would agree with spc2125 that the '05 sounds like the better car to me at this point. The '06 is technically a single owner car, but the history of it being in and out of auto auctions 4-6 times over the last year worries me. Actually being able to talk to the owner of the '05 has been great to hear more of the history on the car first hand especially since he bought it directly from the first owner. I'll ask about the tuning tomorrow too.
How many LGTs have the GTX blue/black seats? I've never seen this option before, although I haven't been looking all that long. I really dig them, even though they don't look like they are powered.