Just a question regarding frame construction of our gen 2 cars. Reading the OEM shop manual it seems like there is no difference in frame construction between the roadster and the Coupe. On the other hand many people say that the Coupe is more rigid/stiff due to having a non detachable roof. However, the GTS roof panel does not seem to be real solid and I am assuming it will flex in various driving situations. So my question would be, if there is a tangible difference in chassis stiffness between the two models?