I wonder how Adrenaline would do with it? And haven't sighted a time for Cargo' here yet.
I'm not a Time Trialer. I put an hour into when it came out, got bored and haven't gone back since. I spend 99% of my time on this game racing in open lobbies. I respect all the aliens, and admire the amount of work/time/effort/dedication they put into their lap times, but I simply do not possess the desire to run laps by myself all day every day.
I will test out the other Takata tune that was posted, and hopefully 2.09 has corrected the online/offline issues, but previously I had found that Seasonal Setups, don't transfer well to Online Lobbies, which is where I do all of my tuning, and all of my setups are based on Online physics. But I think 2.09 has helped make the game physics more consistent across all formats.
As for the Chassis Reinforcement, I agree it helps some cars, but also agree as a general rule of thumb, it appears to add understeer. NASCARS were one of the odd balls, where Reinforcement made a noticeable different in Daytona Lap times, and that's when I started paying a lot more attention to it.
Finally, No, the 06 NSX's aren't any good, in comparison to the older 00, 01, and 03.
Last night I tested the Loctite, Mugen, Mobil and Takata back to back with the exact same setup, and I still personally prefer the Takata for whatever reason.